Forest Insect & Disease Control and Monitoring ...

Forest Insect & Disease Control and Monitoring Activities in Newfoundland and Labrador in 2011 and Outlook for 2012 Compiled by Dan Lavigne Newfoundland and Labrador Department of Natural Resources Forestry and Agrifoods Agency Forest Engineering and Industry Services Division Insect and Disease Monitoring and Control Section ISBN: 978-1-55146-482-4 FEIS Technical Report No. 102

Cover photo: Damage and mortality of 25-year old red pine caused by Scleroderris (EU) Canker – photos taken by Lloyd Belbin in Berry Hill Pond area during 2011 aerial survey.

Forest Insect & Disease Control and Monitoring Activities in Newfoundland and Labrador in 2011 and Outlook for 2012

Compiled by Dan Lavigne

2011

Newfoundland and Labrador Department of Natural Resources Forestry and Agrifoods Agency Forest Engineering and Industry Services Division Insect and Disease Monitoring and Control Section Fortis Building, 4 Herald Avenue P.O. Box 2006, Corner Brook, NL Canada A2H 6J8

ISBN: 978-1-55146-482-4

Permanent Staff – Forest Insect and Disease Control Section Dan Lavigne, Gary Holloway, Lloyd Belbin, Terry Suley (Please see acknowledgements for complete listing of all seasonal and temporary staff, and pest survey aides)

Newfoundland and Labrador Department of Natural Resources Management Districts/Offices In 2011, detection and reporting of insect and disease damage was also provided by DNR Regional and District staff.

i


TABLE OF CONTENTS Page ACKNOWLEDGEMENTS

iii

LIST OF ABBREVIATIONS

iii

LIST OF TABLES

iv

LIST OF FIGURES

v

SUMMARY

vi

INTRODUCTION

1

FOREST INSECT & DISEASE CONTROL ACTIVITIES Forecast and 2011 Treatment Blocks Control Base Operations Weather, Insect Development and Treatment Dates Pre and Post-Spray Sampling and Assessment of Treatment Results Other Control Related Activities in 2011

2 4 4 6 6

FOREST INSECT & DISEASE MONITORING RESULTS AND OUTLOOK FOR 2012 Forest Insect Pests Eastern Hemlock Looper Eastern Spruce Budworm Balsam Fir Sawfly Spruce Beetle Brown Spruce Longhorn Beetle Other Insect Pests Forest Disease Pests Scleroderris (EU – European Strain) Canker of Pines Other Disease Pests

7 10 13 15 16 17 17 20

ASSESSMENTS OF HIGH VALUE AREAS (PLANTATIONS AND THINNINGS)

20

RESEARCH

27

APPENDICES

29

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Appendix A – Comparison of Larval Indices using Ocular versus Head Capsule Measurements. Appendix B – Comparison of tree beating versus branch sampling methods for determining larval development; and pre and post-spray results. Appendix C - Comparison of eastern hemlock looper forecast results using different branch lengths and an alternate rinsing method. Appendix D - Sampling forms and methods used for assessment of high-value areas. Appendix E - Research project updates

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31 33 35 37 43


ACKNOWLEDGEMENTS The experience and input of many individuals is required to monitor and assess insect and disease conditions within the Province and to provide control or protection of the forest resource as needed. The insect and disease protection and monitoring information provided in this report is directly related to the conscientious efforts of Insect and Disease Control Section (IDCS) staff within the Forest Engineering and Industry Services Division (FEIS) of the Newfoundland and Labrador Department of Natural Resources (DNR). Appreciation is extended to all permanent (T. Suley, G. Holloway, L. Belbin), seasonal (B. Hinks, B. Brake, R. Gregory, T. Rideout, L. Callahan, P. Anderson, K. Howell, H. Abbott, G. Critchley, D. Reid, B. McCarthy, B. Bixby, D. Kirby), and temporary staff (J. Short, S. Winsor, J. Pelley, B. Myres, T. Kendell, K. Rumbolt, J. Ryan, M. Benoit, F. Genneaux, F. Atkins, R. Chaffey), and pest survey aides (J. Walsh, L. Walsh, S. Tarbett, R. Leboubon, J. Galliot, H. Baines, S. Deschamps, D. Newman, E. Park, K. Rousseau, R. Ryan, J. Vokey, J. Wellman). Special thanks are also extended to other FEIS, Headquarters and Regional and District staff for their support and assistance to the insect and disease program and in the reporting of forest insect and disease problems found in 2011-12. We’re also grateful for the continued diagnostic support for tree diseases provided by Dr. G. Warren of the Canadian Forest Service (CFS). The cooperation and sharing of information provided by R. Neville and T. Drover of the Canadian Food Inspection Agency (CFIA) for forest pests of quarantine significance was also greatly appreciated. Thanks are also extended to Dr. Lucie Royer (CFS) and Dr. Peggy Dixon (Agriculture and AgriFood Canada) for information provided in 2011. Finally, my thanks to all the members (Basil English; Gary Warren; Tammy Drover; Kirk Greening; Jason Pond; Wayne Kelly; Susan Squires; Lloyd Belbin; Jeff Dewland; Ed Stewart; Barry Linehan; and Jeff Motty) of the Scleroderris (EU) canker working group – your cooperation and assistance is greatly appreciated.

LIST OF ABBREVIATIONS BFS bF bS CFIA CFS HL SBW FEIS IDCS DNR rP SCLEU SERG-I SPBTL wS

Balsam fir sawfly Balsam fir Black spruce Canadian Food Inspection Agency, Agriculture and Agri-food Canada Canadian Forestry Service, Natural Resources Canada Eastern hemlock looper Eastern spruce budworm Forest Engineering and Industry Services Division Insect & Disease Control Section Newfoundland and Labrador Department of Natural Resources Red pine Scleroderris (EU - European Strain) Canker Spray Efficacy Research Group - International Spruce Beetle White spruce

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LIST OF TABLES Page Table 1.

Summary of block opening and treatment dates, areas treated, and litres applied during 2011 HL control program.

5

Table 2.

List of other control related activities conducted in 2011 by airstrip and location.

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Table 3.

Summary of 2011 HL pheromone trap catch results with frequency and percentage of traps shown in arbitrary trap catch ranges based on average moths/trap; maximum trap catch and mean trap catch 2011 being a baseline year for future comparison.

7

Table 4.

Provincial summary of hemlock looper egg survey results by damage/population categories - 2005 to 2011.

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Table 5.

Summary of eastern spruce budworm pheromone trap catch results with frequency and percentage of traps shown in arbitrary trap catch ranges based on average moths/trap; maximum trap catch and mean trap catch - 2000 to 2011.

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Table 6.

Provincial summary of spruce budworm egg mass survey results by damage/population categories 2007 to 2011.

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Table 7.

Provincial summary of balsam fir sawfly egg survey results by damage/population categories - 2000 to 2011.

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Table 8.

Summary of areas assessed during high-value survey by Region, District, silvicultural treatment, and primary tree species.

22

Table 9.

Summary of forest pests identified and their incidence in high-value areas assessed on the island in 2011.

22

Table 10.

Summary of BWA damage observed in bF thinnings assessed during high-value survey in 2011.

24

Table 11.

Research projects partially funded through the Spray Efficacy Research Group – International in 2011.

27

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LIST OF FIGURES Page Figure 1.

Outbreak area with hemlock looper damage.

1

Figure 2.

Tree mortality in forest stand.

1

Figure 3.

Balsam woolly adelgid damage.

1

Figure 4.

Scleroderris damage in red pine plantation.

1

Figure 5.

Area (ha) treated in Newfoundland and Labrador by major forest insect pest.

2

Figure 6.

Seven blocks identified for treatment against hemlock looper based on the 2010 fall forecast survey results.

3

Figure 7.

Comparison of accumulated degree-days (base 3°C) in Corner Brook, NL – 1999, 2002, 2006 and 2011.

4

Figure 8.

Larval development over time assessed in plots used for timing HL treatment blocks.

5

Figure 9.

Reduction in HL larval numbers observed in 2011 treatment blocks.

6

Figure 10.

HL pheromone trapping network and trap catch results for 2011.

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Figure 11.

Area (ha) of moderate-severe defoliation caused by hemlock looper – 1980 to 2011.

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Figure 12.

Hemlock looper egg survey results from the fall of 2011 showing expected damage levels in 2012.

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Figure 13.

General trend (avg. moths/trap) from spruce budworm pheromone trapping results on the island – 2000 to 2011.

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Figure 14.

Eastern spruce budworm pheromone trapping results – 2011.

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Figure 15.

Branch with recovery.

11

Figure 16.

Areas of moderate and severe SBW defoliation mapped around the Goose Bay area in Labrador – 2008 to 2011.

12

Figure 17.

Areas forecast to have SBW defoliation in and around Goose Bay area in Labrador in 2012.

13

Figure 18.

Balsam fir sawfly defoliation in 2011 and forecast for 2012.

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Figure 19.

Areas with damage from spruce beetle in and around Goose Bay area in Labrador – 2006 to 2011.

15

Figure 20.

Trapping results for Brown Spruce Longhorn Beetle in Atlantic Canada – 2006 to 2011.

16

Figure 21.

Damage from Scleroderris (EU) canker observed from the air in 2011.

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Figure 22.

Maps showing indigenous rP, quarantine zone, planted rP and jP, and new Scleroderris (EU) sites.

18

Figure 23.

Maps showing distribution and level of Scleroderris (EU) infection found at ground locations assessed in Berry Hill Pond and White Hills in 2011.

19

Figure 24.

Map showing distribution of plantations and thinnings assessed during 2011 high-value survey.

21

Figure 25.

Map showing overall BWA damage rating determined from assessments of bF trees in thinnings sampled as part of the 2011 high-value survey.

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Figure 26.

Map showing locations and percentage of trees with moose browse recorded during 2011 highvalue survey.

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SUMMARY Eastern Hemlock Looper Control Program: A total of six blocks representing 3733 ha of susceptible forest were aerially treated with the biological insecticide B.t.k. using an application rate of 2 litres/ha. Treatments were made using a Dromader aircraft equipped with AU5000 rotary atomizers and an AG NAV GPS navigational system with Auto Cal Flow Meter and Auto Boom. As per permit requirements signage and public notification of block openings and areas treated was provided. Treatments were conducted over the period July 18 to August 2. Reductions in hemlock looper populations were recorded in all treatment blocks and defoliation was limited to less than 10%. Additional work to maintain equipment and infrastructure needed to support control related activities was also conducted in 2011. Eastern Hemlock Looper (HL): The decline observed in HL populations in recent years continued in 2011. In light of this decline a network of 50 pheromone trapping locations was established in 2011. The number of male moths caught in traps will be used to detect and monitor subtle changes in populations even when populations are low and not detectable by traditional sampling methods for other life stages. In this initial year all traps were positive with an average of 60 moths per trap (range 2 to 358) - these results will serve as a baseline to monitor future trends. Aerial overview surveys conducted to map the severity and extent of defoliation found no moderate-severe defoliation from this insect in 2011. This is the first time that defoliation from this pest has not been recorded on the island since the early 1980’s. For a second year no defoliation was mapped in Labrador following the damage observed from 2006 to 2009. Results from the fall egg survey conducted to forecast population/damage levels for 2012 also indicate that populations have drastically declined with 872 locations having no eggs, 66 have trace counts (1-2 eggs), 22 having low counts (3-9 eggs), and only two locations having moderate counts (10-29 eggs). Given these results, no aerial treatment program to control hemlock looper populations is needed in the Province in 2012, however, monitoring efforts will continue given its significant impact on our forests. Eastern Spruce Budworm (SBW): The last outbreak of this major forest pest ended on the island in the late 1980’s. In contrast, populations of this pest have been active around the Goose Bay area in Labrador for the last five years. Pheromone trap results from a network of 49 locations monitored annually on the island since 2000 indicate that populations of spruce budworm remain low. The aerial overview survey detected no areas of SBW defoliation on the island. Conversely in Labrador ca. 22000 ha of moderate-severe defoliation was mapped. This area is down from the 58000 ha mapped in 2010 with many areas previously defoliated showing signs of recovery. With the exception of a small area of moderate defoliation near Sheshatshiu, the areas defoliated in 2011 shifted further east along the south shore of Lake Melville in the vicinity of the English River. Fall egg mass survey results indicate that populations will remain active around the Goose Bay area in 2012 with 19 locations forecast to have light damage, 2 locations (S shore of Lake Melville near English River; 16 km SE of Goose Bay (Mud Lake)) forecast to have moderate damage, and one location (8 km E of Goose Bay) forecast to have severe damage. No concerns regarding impacts and the need for control were expressed by District 19 staff. On the island three locations (Sally’s Cove, Zinc Mine Rd., Botwood Hwy.) with higher trap catches were sampled for egg masses. Only two egg masses (light defoliation forecast) were found at the Botwood location. Populations of this important insect pest will continue to be monitored in 2012, especially in light of the increasing populations occurring in the Province of Quebec. Balsam Fir Sawfly (BFS): The last outbreak of this pest occurred on the island from 1991 to 2009. At present there is no pheromone lure for monitoring low density populations of this insect. One of the primary means for detecting this pest is through observations of damage made by IDCS staff and reports received from DNR District staff, forest industry or the general public. In 2011, damage from BFS was reported by District 7 staff on the Connaigre Peninsula. An aerial overview survey conducted by IDCS staff detected ca. 13000 ha of moderate to severe defoliation in scrub forest stands in this area. Small localized pockets of BFS defoliation were also observed from the ground by IDCS staff in west central portions of the island near the SE border of Gros Morne National Park. Results from the fall egg mass survey indicate that populations of this pest will remain high and expand slightly on the Connaigre Peninsula in 2012. Once again much of this area is in scrub forest stands. One moderate forecast point ca. 6 km N of St. Albans was found within an area with thinnings. In west-central NL, this pest will also remain active with 7 locations forecast to have light damage and one location N of Bonne Bay Little Pond forecast to have severe defoliation. No control for this pest will be conducted; however, areas will continue to be monitored in 2012 for defoliation and fall egg counts. Spruce Beetle (SPBTL): Aerial overview surveys conducted on the island and in Labrador continue to detect SPBTL damage in areas with mature and overmature white spruce. On the island damaged trees continue to found in the Humber River valley. In Labrador the areas (Grand Lake road and Mud Lake/Kenemu River) with severe defoliation and dead trees have grown from ca. 11000 ha in 2005 to 41000 ha in 2011. Within this area there is now older mortality (i.e. grey trees and fallen timber) and fewer yellow or red trees indicating more recent attack. Fortunately much of this area appears to be in scrub stands with poor sites. Brown Spruce Longhorn Beetle (BSLB): This is an invasive alien species that attacks all spruce species. It was first introduced into the Halifax area in the late 1980’s. Despite efforts to eradicate and contain this pest it has now spread into other areas of Nova Scotia and was found for the first time in Kouchibouguac National Park in New Brunswick in 2011. Firewood brought in by campers is suspected as being the source of this most recent find. For invasive species, identifying high-risk commodities and pathways is extremely important. For BSLB these commodities include spruce round wood with bark, firewood and wood packaging materials. In 2011, the CFIA conducted trapping at 19 high risk sites including ports and wood processing facilities – no BSLB were found. The close proximity of positive finds in Atlantic Canada certainly reinforces the need to remain vigilant. Although the movement of high-risk commodities is regulated by the CFIA, additional education should be considered to reduce the risk of introducing this pest into the province.

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Forest Insect & Disease Control and Monitoring Activities in Newfoundland and Labrador in 2011 and Outlook for 2012 Other Insect Pests: European pine shoot moth continues to be a common pest found in rP plantations. In the St. Anthony area, the hairy poplar sawfly caused severe defoliation of balsam poplar. In the Goose Bay area, defoliation caused by a grasshopper identified as the Huckleberry Spur-Throated Grasshopper, was observed on young spruce trees in a plantation. Damage by grasshoppers on planted trees, although less common, was also found on planted rP and jP in Manitoba in the 1970’s. Scleroderris (EU) Canker: This invasive alien species is a serious disease of hard pines. It causes tree mortality in both young and mature trees with rP being the most susceptible. In 2011, aerial overview surveys detected damage in 25 year old rP plantations in the Berry Hill Pond and White Hills areas. Follow-up ground sampling and examination of samples by Dr. Gary Warren of the CFS and staff from the CFIA confirmed the presence of this disease in both these areas, as well as, a jP site in Conne River Pond. These new find are well outside of the existing quarantine zone (Avalon Peninsula) for this disease. Survey work conducted in 2011 for this disease is summarized. A Scleroderris (EU) canker working group was also formed to coordinate and provide expertise on dealing with this disease. If left unchecked it has the potential to spread into other rP areas. At risk are indigenous or native rP stands of ecological significance and planted rP. To date ca. 3.1 million dollars has been invested in the latter. A summary of work to be conducted in 2012, including a directed SCLEU survey to look at the distribution and occurrence of this disease, is provided. Other Disease Pests: Red band needle blight was also detected in rP plantations with SCLEU. On the island and in Labrador spruce needle rust was also prevalent with heavy infection reported in the Grand Lake Road area near Goose Bay and areas around Labrador City. Assessments of High-Value Areas: Significant annual investments have been made in silviculture. At present there are ca. 250000 ha of high-value areas (plantations and thinnings). These represent ca. 20% of the 1.3 million ha of forest considered to be productive and operationally available for harvest on the island. At present there is no routine or systematic assessments (i.e. 5 or 10-yr) made in these areas following their establishment. Given the above, a survey to monitor forest pest conditions in high-value areas was initiated in 2011. Details related to the sampling protocols used can be found in Appendix D. A total of 132 (97 thinnings; 35 plantations) locations were assessed. Forest pests were identified and their incidence recorded. On bF the most common pest damage observed was twig attack by the balsam woolly adelgid, moose browse, and damage from the Balsam gall midge. On spruce, the most common pest occurrences were spruce bud midge, needle rust, and moose browse. This survey also provided the opportunity to conduct additional assessments to record the levels of balsam woolly adelgid (BWA) damage observed in thinned stands. Random assessments of BWA damage on 50-75 trees in each stand were made in 91 of the 97 thinnings. Thinnings assessed in Districts 11, 12 and 14 had higher levels of damage. In contrast, thinnings in Districts 9, 10, 15, and 16 had no damage or light damage. The lack of any reports of BWA damage in thinnings assessed in Districts 17 and 18 also indicates that BWA is not very active on the northern peninsula. Given the number of reports of moose browse damage, the locations with moose browse and the percentage of trees affected at each location was examined. Moose browse was recorded in Districts 9, 10, 11, 15 and 16. In contrast, no incidence of moose browse damage was recorded in high-value areas assessed in Districts 12, 13 and 14. In 2012, forest pest monitoring work in silvicultural areas will be continued with efforts made to assess plantations and thinnings in areas not assessed in 2011, while maintaining a level of monitoring across the Province. Research: The department continues to participate in research projects through its membership with the Spray Efficacy Research Group International (SERG-I). It allows SERG-I members to work cooperatively on research projects through the sharing of expertise, and financial and in-kind resources to achieve common goals in the areas of spray efficacy and integrated pest management. In 2011, five projects were partially funded with results reported in Appendix E. The most significant research contribution made was funding for a research project to determine and evaluate the major ecological factors affecting the population dynamics of HL with the overall purpose of providing critical information required to predict HL phenologies and population dynamics in a changing environment. This information will be extremely valuable as we try to manage or mitigate the impacts of this major forest pest in the future. The department also continues to contribute to forest pest research and forest pest management in general through its involvement with the National Forest Pest Strategy and Forest Pest Management Forum. Identifying research priorities and participating in research initiatives continues to be an important component in providing the information and tools needed to protect our forests through an integrated pest management approach. Other Special Project/Tests in 2011: A number of in-house trials and projects were conducted to compare and test existing and different sampling methods used to monitor insect development, conduct pre and post-spray sampling, and forecast pest populations. The purpose of these trials was to evaluate and improve methods were appropriate. Results are summarized in Appendix A, B, and C and will assist in all the above areas. Additional attention to headcap widths when visually determining instars should improve measurements of larval development. Advantages were observed in using a branch sampling method instead of tree beatings for assessments of larval development and efficacy. Information found on the number of HL eggs on different parts of a branch indicate that for now a larger branch should be used, however, the branch length probably does not need to exceed 150cm to correlate with historical thresholds of total eggs versus defoliation. The testing of different lab washing techniques found no difference in the number of eggs removed from branches when using 20 versus 10 litres of solution, and the rinsing of branches found additional eggs 50% of the time – these will lead to changes in lab processing/washing methods.

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Forest Insect & Disease Control and Monitoring Activities in Newfoundland and Labrador in 2011 and Outlook for 2012 Introduction An essential part of good forest stewardship is the protection of our forests from uncontrolled outbreaks of forest insect and disease pests (Figure 1). These pests can cause widespread growth losses and tree mortality. Apart from the direct impact on trees and wood supply, there are also adverse impacts on non-timber values such as ecosystem processes, aquatic and terrestrial wildlife habitats, recreational use and forest aesthetics. As trees die and forest stands open up, more sunlight reaches the ground and dries out materials increasing the risk of fire in these insect killed areas (Figure 2). In the 1970’s the failure to actively pursue a forest protection program against the eastern spruce budworm (Choristoneura fumiferana (Clemens)) resulted in the loss Figure 2. Tree mortality in forest stand. of 50 million cubic metres of balsam Figure 1. Outbreak area with hemlock looper damage. fir (Abies balsamea) and black spruce (Picea mariana). This represented a 25-year wood supply to the forest industry. Beyond the impacts that occur in our natural forest, impacts can also occur in high-value areas (i.e. plantations, thinnings) established as part of our reforestation program. Millions of dollars has been invested in these high-value areas which now represent about 19 to 20% of the productive forest land-base. These areas are important to the long-term sustainability and health of our forests. Beyond the threat from native pests, in today’s global economy there are also increased risks with respect to the accidental introduction of invasive insect and disease species from other parts of the World. Such introductions can cause not only direct impacts on our forests, but they can have indirect economic impacts through regulations placed on domestic, national, or international movement of goods. We can already see adverse affects on our forest from introduced pests such as the Balsam Woolly Adelgid (Adelges piceae Figure 3. Balsam woolly adelgid damage. (Ratzeburg)) (Figure 3), and the European strain of a tree disease called Scleroderris canker ((Gremmeniella abietina Lagerb.) M. Morelet.) (Figure 4). There are also new threats from other invasive species such as the brown Figure 4. Scleroderris damage in red pine plantation. spruce longhorn beetle (Tetropium fuscum) and gypsy moth (Lymantria dispar). These pests are already present in other Atlantic Provinces. The threats and impacts posed by these native and invasive forest pests highlights the need for having an active monitoring program to know the status of these pests and provide control when needed. Control - In 1974 the Newfoundland and Labrador Department of Natural Resources (DNR) took over the responsibility for monitorng and conducting control programs for all major forest pests. Pesticides registered under the Federal Pest Control Products Act have been applied aerially to control populations and protect our forests from the damage and impacts caused by these pests. From 1977 to 1985, and in 1992 and 2010 aerial control programs were conducted against the eastern spruce budworm (Figure 5). In 1985 to 1990, 1992 to 2005, and 2007 to 2011 aerial control programs were conducted for eastern hemlock looper (Lambdina fiscellaria fiscellaria (Guenée)

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(Figure 5). In 1998 and 1999 and from 2001 to 2003 and 2006 to 2009 aerial control programs were conducted for the balsam fir sawfly (Neodiprion abietis (Harr.)) (Figure 5). The Province has been using Bacillus thuringiensis (var. kurstaki) (B.t.k.), a commercial biological pesticide containing a naturally occuring bacterium since 1977 to control populations of eastern spruce budworm (SBW) and eastern hemlock looper (HL). B.t.k. contains a naturally occurring bacterium found in soils, water and on plants. It is used to control a variety of pests in forestry, agriculture, urban, and organic applications – including the protection of food crops. Monitoring - Different survey methods are required to monitor and forecast insect and disease populations and damage, and. time and assess treatments. The methods used are directly related to the objectives of the surveys, the populatIons being monitored, the pest’s biology, Figure 5. Area (ha) treated in Newfoundland and Labrador by major forest insect pest. and knowledge of the relationship between pest numbers and subsequent damage. For some pests the latter is well established and for other it’s still poorly understood. For insects that over winter in the egg stage, forecast surveys can be conducted to predict population and damage levels by sampling appropriate locations for eggs or egg masses, depending on the female’s egg laying habits. For insect that over winter in the larval stage, sampling can likewise be conducted to predict populations and damage based on the number of larvae found. These forecast surveys essentially identify the areas where treatment may be required to reduce populations and damage. Surveys of larvae can also be conducted during the insect’s active feeding period to determine their larval development – this a key piece of information needed to time treatments. The assessment of larval numbers before and after treatment in treated and untreated areas is also used to assess treatment results. Aerial overview surveys provide the means to map and categorize the extent and severity of damage (i.e. defoliation and mortality) associated with outbreaks of various forest pests. The identification and artificial synthesis of sex pheromones for a number of forest insects has also led to the use of pheromone-baited traps as another technique for monitoring forest pests. To attract a mate unique pheromones or scents are emitted by female insects to attract males of the same species. Male moths caught in these traps can be used to detect and monitor subtle changes in populations even when populations are very low and not detectable by traditional sampling methods for other life stages. The number of insects captured in a trap can be influenced by a number of different factors including the type of lure used, its concentration, the trap design and the insect species itself. As with any monitoring technique, the results obtained with pheromone trapping must be carefully interpreted until changes in trap catches and thresholds associated with rising populations and subsequent damage are better understood. Moth counts considered to be biologically significant for one species may not be significant for another and may differ by several orders of magnitude. Consequently, the absolute number of insects in a trap for a particular species may not be as important as the trends observed over time. In the future these trends should assist in the early detection of rising populations of important forest pests prior to them reaching outbreak status. Specific trap thresholds may also help to determine when other more traditional forecast methods should be used within specific areas to help in the prediction and delineation of population and damage levels expected in the ensuing year.

Forest Insect & Disease Control Activities in 2011 Forecast and 2011 Treatment Blocks A decline in HL populations was apparent from the 2010 fall forecast (egg) results (see HL forecast results – page 8). Despite this decline a number of small areas were forecast to have moderate defoliation. These areas were subsequently blocked and approved for aerial control under a Pesticide Permit and License issued by the Department of Environment and Conservation. A total of seven blocks representing 4277 ha of susceptible forest were scheduled for treatment using the biological insecticide B.t.k .(Figure 6). A press release

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with information on the 2011 control program was provided to the public over the period June 25 -29 via the Department of Natural Resources (DNR) website and newspapers. Digital files with the boundaries and flight lines of the treatment block were prepared for

Figure 6. Seven blocks identified for treatment against HL based on the 2010 fall forecast survey results.

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subsequent use in the navigational equipment of the spray aircraft. License requirements also dictated that signs showing the areas to be treated be placed near treatment blocks having public access – these signed were placed the week of July 4th.

Control Base Operations To facilitate the treatment of the seven blocks, DNR set-up and operated one control base in Springdale in 2011. Base set-up began on June 21st and was operational from July 1st to August 2nd. Similar to control setups in previous years, the base had aircraft fuel storage and insecticide storage areas, security offices, and all applicable environmental and emergency equipment in the case of an accidental spill. As per regulations and permit conditions, security was present 24-hours a day, 7-days a week throughout the operation. An M-18 Dromader aircraft from Supermarine Aircraft Inc. from St.Thomas, Ontario was contracted to conduct the aerial treatments. This aircraft was equipped with Micronair AU5000 rotary atomizers, and an AG NAV GPS navigational system with Auto Cal Flow Meter and Auto Boom - the swath width used was 76 meters. A helicopter was also contracted and stationed at the base to provide aerial support for supervision of all spray missions. It was also used by field crews responsible for conducting development and pre and post-spray surveys in blocks inaccessible by road. Clean-up and dismantling of the control base was completed by August 16th.

Weather, Insect Development, and Treatment Dates The development of insects is tied closely to weather, specifically cumulative temperatures above a specific threshold. A common temperature threshold used for many insects is 3ºC. Degree-days using this threshold are calculated on a daily basis using the formula ((maximum temperature + minimum temperature)/2) -3 and accumulated over the course of the season. Separate accumulated degreedays thresholds are then related to the seasonal phenology or biological development of insects. For example, in Figure 7 accumulated degree-days of 356 correspond to peak 2nd instar of HL larvae. To control HL populations the pesticide label for B.t.k. recommends that blocks be treated when peak second instar is reached. Cooler temperatures during the summer delayed larval development slightly when compared to a year with average or normal temperatures (i.e. 2006) and a year with warmer temperatures (1999). Degree-day accumulations based on weather information collected from the Corner Brook area indicated peak 2nd instar was reached in the Corner Brook area on or around June 28th (personal communication, Dr. Lucie Royer, 2011). 1600

1400

1200 1999 2002 1000

2006

DD3

2011 DD mean egg hatch

800

DD mean 2nd DD mean 3rd DD mean 4th

600

DD mean pupae DD mean adults 400

200

0 1/0

1/30

2/29

3/30

4/29

5/29

6/28

7/28

8/27

9/26

10/26

date

Figure 7. Comparison of accumulated degree-days (base 3°C) in Corner Brook, NL – 1999, 2002, 2006 and 2011.

The treatment blocks, however, where at higher latitudes and elevations than the Corner Brook. Surveys to monitor HL larval development and pre-spray populations began July 14th. Larvae were collected and examined using the traditional tree beating method. The total number of larvae from three beat trees was recorded. An ocular method based on experience in working with this pest was then used to determine larval instars. In 2011, these population counts and assessments of larval development were compared to an alternate method that employed branch sampling of marked trees to assess populations and the collection of larvae for subsequent examination

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under a dissecting microscope to measure head capsule widths to determine larval instars. Results of these comparisons can be found in Appendix A and B. Larval indices were recorded over time for different plots and treatment blocks (Figure 8). Survey results indicated that blocks were not biologically ready for treatment 4.5 until July 18 to 27th (Table 1). 4

3.5

101-1

102-1

102-3

103-1

104-1

104-2

104-3

105-1

106-1

106-2

106-3

106-4

107-1

107-2

107-3

Larval Index

3

2.5

2

1.5

1

0.5

18-Aug

11-Aug

10-Aug

3-Aug

2-Aug

1-Aug

29-Jul

27-Jul

26-Jul

25-Jul

23-Jul

22-Jul

21-Jul

20-Jul

19-Jul

18-Jul

14-Jul

0

Date

As per permit requirements, public notification of block openings and areas treated was provided via DNR’s website. Low pre-spray counts in block 101 resulted in only six of the seven blocks being treated. Four and half blocks (102, 103, 105, 107, west half of 104) or 2923 ha were treated with one application of B.t.k. (Foray 76B) at 2 litres/ha. One and half blocks (810 ha) received two applications of B.t.k. at the same rate. The decision to apply a second application to these blocks was based on a significant number of larvae still being present 5-7 days after the first application. Treatment dates, the areas treated and number of litres applied are also summarized in Table 1.

Figure 8. Larval development over time assessed in plots used for timing HL treatment blocks.

Table 1. Summary of block opening and treatment dates, areas treated, and litres applied during 2011 HL control program. Block #

Location

Area (ha)

Volume (litres)

101

Wild Cove Pond

544

1088

102 103

Open 1st

Red Cliff Pond Cross Country Pond

1219 238

2438 476

July 27 July 23

**104 (East) 104 (West) 105

North Twin Lake

525

2100

July18

North Twin Lake East of Goose Pond

525 153

1050 306

**106

Kitty’s Brook

285

107

Victoria Lake TOTALS:

Date Treated *(not treated low populations) July 27(pm) 29(pm) 30(pm) July 30 (am)

Lines Treated

1-23

July18 July 21

23-45 All

1140

July 21

July.23 (am)

All

788

1576

July 24

July.25 (am)

1-36

4277

10174

5

Date Treated

Lines Treated

July 30

Aug.1(pm)

1-23

July 30

Aug. 2 (am)

25-21 35-33 26-32 1-11

Part-July.21(pm) RemainderJuly.22(pm) July.23 (am)

** Yellow rows indicate portions of blocks or blocks treated with two applications.

Open 2nd


Pre and Post-Spray Sampling and Assessment of Treatment Results

A reduction in the total number of HL larvae found in post-spray samples was recorded in all treatment blocks (Figure 9). Percent reductions in populations ranged from 47.8% to 95.2% (102 – 95.2%; 103 – 47.8%; 104 – 54.7%; 105 – 68.2%; 106 – 95.1%; and 107 – 80.4%).

#of Larvae

Pre and post-spray assessments of larval populations were conducted in plots within treatment blocks using the traditional tree beating method. Postspray assessments were done 5-7 and 10-14 days after treatments. The 105 same tree beating and branch 100 95 sampling methods used to determine 90 pre-spray populations (i.e. total 85 number of HL larvae found) were also 80 Pre-spray used to determine populations 75 following treatment. Unfortunately, 70 given the decline in HL populations, Post 1 App. 65 (5-7 days) no suitable untreated controls could 60 be found to assess natural mortality 55 Post 1 App. levels. 50 (10-14 days) 45 40 35 30 25 20 15 10 5 0

Post 2 App. (5-7 days) Post 2 App. (10-14days)

102

103

104

105

106

The percent current defoliation Block # observed in all blocks was less than ten percent. Figure 9. Reduction in HL larval numbers observed in 2011 treatment blocks.

107

Other Control Related Activities in 2011 Additional work to maintain equipment and infrastructure must be conducted each year to ensure operational readiness to carry-out control actions as needed. As needed, Insect and Disease Control (IDCS) staff also provide assistance to other programs within the Forest Engineering and Industry Services Division (FEIS), DNR and other departments. Table 2 provides a listing of other control related activities conducted in 2011. Table 2. List of other control related activities conducted in 2011 by airstrip or location. Airstrip/Location

Description of activities conducted

Main Brook Port au Choix

Brush cut and cleared at both ends of airstrip, and repaired/painted security building Maintained concrete pesticide berm, repaired/painted security building, painted storage shed, transported and painted new fuel tank. Painted storage building, maintained fuel set-up, sealed and striped aircraft ramp, removed operations trailer from site, and site clean-up. Transported pesticide used and left over from control program to and from storage bunker; replaced old septic/water system on crew trailer; maintained/painted crew trailer, office, and storage building; removed glass and vegetation on aircraft parking and taxi ramps; and cleaned and restored pesticide storage bunker. Installed command trailer, and resealed aircraft parking area and run-up ramp. Installed siding on storage building. Removed fuel system and moved concrete barrier. Transport of equipment used for control program to and from hanger, annual maintenance of all spray equipment (pumps, hoses, tanks, support vehicles); floor painted; installed shelving; insulated pump storage room; and worked on trailers and new fuel bowser. Maintenance on lab and wash facility. Assisted FEIS Roads Section with transport of culverts and bridging materials. Use of boom truck to remove abandoned vehicles and equipment.

Deer Lake Stephenville Buchans Goose Bay Port Hope Simpson Gander (Hanger 21) Pasadena Field Station Pynns Bk Eastern Region

6


Forest Insect & Disease Monitoring Results and Outlook for 2012 Forest Insect Pests Eastern Hemlock Looper – Since the collapse of eastern spruce budworm populations in the late 1980’s, the HL has been the major forest pest in Newfoundland and Labrador. Large outbreaks of HL are common on the island and were also seen for the first time at unprecedented levels in Labrador in 2006 to 2009. High populations and heavy feeding damage by the larval stages of this pest can kill balsam fir trees in a single year given the insects’ wasteful feeding habits. This includes not only consuming entire needles, but also partially eating both current and old foliage causing them to die. Areas with high populations have been treated aerially (Figure 5) to avoid widespread tree mortality and growth losses and minimize impacts to other forest values. Pheromone trapping survey: Given the decline observed in HL populations within the Province in recent years, the decision was made to establish a network of pheromone traps to help monitor low density populations. As a starting point, a subset of 50 locations was established on the island within susceptible balsam fir stands also used to forecast HL populations during the fall egg survey. This will provide an opportunity to compare pheromone trap catches to egg densities and damage in the future. At each location, one Unitrap pheromone trap containing a 10 ug HL lure and one Vaportape killing strip was placed. Trap placement was done from Aug. 29th to Sept. 2nd, prior to adult moth activity. Traps were subsequently checked for adult moths during the period Sept. 19th to Sept. 23rd. Final trap collection was conducted during the fall egg survey. The total number of HL moths found at each location was recorded with 2011 becoming a baseline year for these 50 locations (Figure 10, Table 3). All traps were positive (i.e. caught at least one moth) with trap catches ranging from 2 to 358 moths/trap (mean trap catch of 60.4 moths). The predominantly low trap catches observed suggests a continued decline in HL populations. This was confirmed by fall egg survey results (page 8). Although only based on one year of data, it appears to indicate that there is little threat of HL damage at trap Figure 10. HL pheromone trapping network and trap catch results for 2011. catches < 400 moths/trap. Plans for 2012 include increasing the pheromone trapping network on the island to 100 locations and with the assistance of District staff conduct trapping in areas of Labrador previously impacted by this insect. Table 3. Summary of 2011 HL pheromone trap catch results with frequency and percentage of traps shown in arbitrary trap catch ranges based on average moths/trap; maximum trap catch and mean trap catch - 2011 being a baseline year for future comparison. Year 2011 2012

Number of locations

Traps/ Location

% of positive locations

50 100

1 2

100% *tbd

Avg. number of moths/trap by location in ranges 0

1-50

51-100

101-200

201-400

401-800

>800

Maximum trap catch

0 *tbd

30 (60.0%) *tbd

9 (18.0%) *tbd

9 (18.0%) *tbd

2 (4.0%) *tbd

0 *tbd

0 *tbd

358 *tbd

* tbd – to be determined through trapping in 2012.

7

Mean trap catch 60.4 *tbd


2010

2008

2006

2004

2002

2000

1998

1996

1994

1992

1990

1988

1986

1984

1982

1980

Area of M-S Defoliation (ha)

220000 Aerial Overview Survey: Aerial overview surveys to detect Island 200000 and map the severity and extent of damage caused by major Labrador 180000 forest pests were conducted July 9-10th and August 14-18th in 160000 140000 Labrador and from August 19th to September 9th on the island. 120000 Approximately 33 and 52 hours of flying were conducted over 100000 susceptible forest areas in Labrador and the Island, 80000 60000 respectively. For a second year in a row no defoliation from HL 40000 was observed in Labrador following an outbreak that caused 20000 0 moderate to severe (M-S) defoliation in 2006 (593 ha), 2007 (8848 ha), 2008 (9392 ha) and 2009 (4228 ha). On the island, YEAR no visible defoliation from HL was observed - this is the first time that M-S defoliation has not been mapped or recorded for Figure 11. Area (ha) of moderate-severe defoliation caused by hemlock this pest since the early 1980’s (Figure 11). The lack of any looper – 1980 to 2011. visible defoliation from this insect again indicates that populations are on the decline. With large increases in populations recorded every 14-16 years, if the cycle repeats itself the next large increase would occur in 2016. In the interim localized outbreaks of this pest may occur in areas of the Province.

Fall Egg Survey: On Sept. 8th an e-mail was sent to DNR Regional/District staff and forest industry personnel asking them to report any HL moth activity, in particular large numbers of moths around street lights, businesses, harvesting equipment etc. No reports of any moth activity were provided – this combined with no visible defoliation from the aerial overview survey and low pheromone trap results led to a decision to reduce the sampling intensity for the fall forecast survey from 1232 locations in 2010 to 997 locations in 2011. The fall survey, which involves the collection of branch samples, commenced on Oct.12th and finished on Dec. 8th. Sixteen out of 980 plots were dropped for various reasons. A total of 962 and 35 plot locations were done on the island and in Labrador, respectively. In 2011, all egg survey plots were flagged, and new GPS coordinates (landing/roadside, stand) collected. In each plot three trees were also selected and marked. Collected branch samples were delivered to the Pasadena Field Station and processed using established protocols that use a 2% solution of Javex to help dislodge eggs from the branches. Processing was conducted over the period October 14th to December 23rd. Testing to examine the number of eggs found on different portions of the branch, the addition of a rinse method, and smaller buckets with less water were incorporated in the processing. Results of these tests can be found in Appendix C. Eggs removed from branches were examined to determine if they were healthy or parasitized and the total number of healthy eggs per location used with historical thresholds developed by the CFS for HL in NL to forecast population/damage levels for 2012. Results (Table 4; Figure 12) indicate that HL populations have indeed collapsed on the island with 872 locations having no eggs, 66 having trace counts (1-2 eggs), 22 having low counts (total 3-9 eggs), 2 having moderate counts (10 to 29 eggs), and no locations having severe counts (>29 eggs). In Labrador HL populations which collapsed in 2009, remain low with no eggs found at the 35 locations assessed. This is a stark contrast from the percentage of plots (31.9%) assessed in 2006 that were forecast to have M-S defoliation. Table 4. Provincial summary of hemlock looper egg survey results by damage/population categories - 2005 to 2011. Year 2011

2010

2009

2008

2007

2006 2005

Provincial Area

Number of locations

Island Labrador Total Island Labrador Total Island Labrador Total Island Labrador Total Island Labrador Total Island Labrador Total Island

962 35 997 1172 60 1232 1193 62 1255 1207 134 1341 1090 125 1215 1037 119 1156 1060

% of positive locations 9.4% 0.0% 9.0% 24.1% 8.3% 23.4% 28.9% 0.0% 27.5% 30.2% 9.0% 28.1% 34.0% 44.0% 35.1% 26.7% 63.9% 30.5% 12.9%

Total number of healthy eggs per location in damage thresholds Nil Trace Light Moderate Severe 0 1-2 3-9 10-29 30+ 872 (90.6%) 66 (6.7%) 22 (2.3%) 2 (0.2%) 0 (0.0%) 35 (100%) 0 0 0 0 907 (90.4%) 66 (6.6%) 22 (2.2%) 2 (0.2%) 0 889 (75.9%) 191 (16.3%) 81 (6.9%) 9 (0.8%) 2 (0.2%) 55 (91.7%) 3 (5.0%) 2 (3.3%) 0 0 944 (76.6%) 194 (15.7%) 83 (6.7%) 9 (0.7%) 2 (0.2%) 848 (71.1%) 151 (12.7%) 110 (9.2%) 47 (3.9%) 37 (3.1%) 62 (100%) 0 0 0 0 910 (72.5%) 151 (12.0%) 110 (8.8%) 47 (3.7%) 37 (2.9%) 842 (69.8%) 161 (13.3%) 118 (9.8%) 49 (4.1%) 37(3.1%) 122 (91.0%) 11 (8.2%) 1 (0.7%) 0 0 964 (71.9%) 172 (12.8%) 119 (8.9%) 49 (3.7%) 37 (2.8%) 719 (65.9%) 178 (16.3%) 113 (10.4%) 51 (4.7%) 29 (2.7%) 70 (56.0%) 24 (19.2%) 11 (8.8%) 10 (8.0%) 10 (8,0%) 789 (64.9%) 202 (16.6%) 124 (10.2%) 61 (5.0%) 39 (3.2%) 760 (73.3%) 174 (16.8%) 78 (7.5%) 23 (2.2%) 2 (0.2%) 43 (36.1%) 15 (12.6%) 23 (19.3%) 11 (9.2%) 27 (22.7%) 803 (69.5%) 189 (16.3%) 101 (8.7%) 34 (2.9%) 29 (2.5%) 923 (87.9%) 86 (8.1%) 40 (3.8%) 9 (0.8%) 2 (0.2%)

8

Maximum Eggs 14 0 14 57 6 57 413 0 413 413 4 413 405 108 405 56 137 137 48

Total Eggs

Mean per location

209 0 209 819 15 834 5154 0 5154 5238 17 5255 4713 893 5606 1058 2210 3268 493

0.22 0.00 0.21 0.70 0.25 0.68 4.32 0.00 4.12 4.34 0.13 3.92 4.32 7.14 4.6 1.02 18.57 2.83 0.46


Figure 12. Hemlock looper egg survey results from the fall of 2011 showing expected damage levels in 2012.

The two moderate counts, one 11km NE of Daniel’s Harbour and one 0.5km S of the Stephenville Rt. 460 exit were both on the low end of the moderate range. Although these areas will be watched in 2012, they are unlikely to pose a significant threat given the declining trend and collapsing populations. Given these results, no aerial treatment program to control HL populations is needed in the Province in 2012.

9


Eastern Spruce Budworm – The eastern spruce budworm (SBW) is another major forest pest that has caused major impacts on NL’s forests. The last outbreak of this insect pest began on the island in the early 1970’s and ended in the late 80’s. During that period largescale aerial control programs (Figure 5) and salvage operations were needed to mitigate impacts. Since then populations of this pest have remained low on the island. In contrast, populations of this insect have been active in Labrador for the last 5 years, particularly around Goose Bay. Given the growth losses and tree mortality to spruce and fir that occurs during outbreaks, the Province remains committed to monitoring for this important pest. The need to maintain a monitoring effort has been heightened by the increases noted in SBW populations in the Province of Quebec since 2006. Populations have increased steadily reaching more than 600 000 hectares in 2010, 1.6 million hectares in 2011, with additional increases expected in the future. Unlike previous outbreaks in Quebec, the most recent outbreak has started further north along the north shore of the St. Lawrence River and north of Lac St-Jean. Obviously one of the concerns is that as these outbreaks continue to grow there is an increased likelihood or potential for flights of adult moths from Quebec reaching NL. Radar tracking studies and observations in the 1970’s indicated that with favourable winds and meteorological conditions SBW moths from other Provinces were making their way to NL. Female moths in these flights still had 40-50% of their egg laying compliment. The resulting SBW populations from the combined egg laying from both local and immigrant moths eventually leads to populations overcoming natural controls resulting in outbreaks. Pheromone trapping survey: A small network of 49 pheromone trapping locations was established on the island beginning in 2000 to help with the monitoring of low density SBW populations. This trapping network will also help in the detection of sudden increases in trap catches along the leading edge or western portion of the island where adult moth may be blown in.

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

Avg. moths/trap

100 In 2011, two Multi-Pher ® I traps containing a 330ug SBW 80 flex lure from Contech Enterprises Inc. and a Vaportape 60 killing strip were placed at each of the 49 locations. Traps th 40 were placed from June 29 to July 16 and retrieved from 20 August 20th to September 16th. The traps were checked . several times between trap placement and retrieval. 0 Trapping results indicate that populations of SBW remain low. Although a general increase in the average number of Year moths per location was observed in 2007 and 2009, moth catches have fortunately declined in the last two years Figure 13. General trend (avg. moths/trap) from spruce budworm pheromone (Table 5 , Figure 13). Despite this general decline, there trapping results on the island – 2000 to 2011. were three locations (Figure 14) with higher trap catches (Sally’s Cove - 370 moths/trap; Zinc Mine Road – 193 moths/trap; Botwood Highway - 155 moths/trap). These locations were identified for follow-up sampling during the fall forecast survey.

Table 5. Summary of eastern spruce budworm pheromone trap catch results with frequency and percentage of traps shown in arbitrary trap catch ranges based on average moths/trap; maximum trap catch and mean trap catch - 2000 to 2011. Year 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000

Number of locations

Traps/ Location

49 47 49 50 48 48 43 39 35 37 39 35

2 2 2 2 2 2 2 2 2 2 2 2


Avg. number of moths/trap by location in ranges 0

>0-10

>10-50

>50-100

>100-200

>200300

>300

4 (8.2%) 6 (12.8%) 1 (2.0%) 0 2 (4.2%) 31 (64.6%) 12 (27.9%) 9 (23.1%) 15 (42.9%) 14 (37.8%) 7 (17.9%) 12 (34.3%)

38 (77.6%) 23 (48.9%) 13 (26.5%) 17 (34.0%) 4 (8.3%) 17 (35.4%) 21 (48.8%) 25 (64.1%) 18 (51.4%) 15 (40.5%) 24 (61.5%) 20 (57.1%)

3 (6.1%) 15 (31.9%) 24 (49.0%) 23 (46.0%) 23 (47.9%) 0 4 (9.3%) 4 (10.3%) 2 (5.7%) 8 (21.6%) 8 (20.5%) 3 (8.6%)

1 (2.0%) 1 (2.1%) 4 (8.2%) 4 (8.0%) 10 (20.8%) 0 4 (9.3%) 1 (2.6%) 0 0 0 0

2 (4.1%) 0 3 (6.1%) 3 (6.0%) 6 (12.5%) 0 1 (2.3%) 0 0 0 0 0

0 1 (2.1%) 2 (4.1%) 1 (2.0%) 1 (2.1%) 0 1 (2.3%) 0 0 0 0 0

1 (2.0%) 1 (2.1%) 2 (4.1%) 2 (4.0%) 2 (4.2%) 0 0 0 0 0 0 0

Maximum trap catch 370 435 1701 445 440 7 209 86 24 31 48 28

Mean trap catch 19.6 24.6 83.8 48.5 66.6 0.6 18.2 6.2 2.6 5.5 6.3 3.9

Given the increase in SBW populations in Quebec, the plan in 2012 is to increase the SBW pheromone trapping network on the island from 49 to 100 locations. With the assistance of District staff, a small subset of traps on the west coast will be monitored routinely to

10


record trap catches over the course of the season. This information will be compared to local weather conditions and storm fronts to determine if other adult moths are being caught outside of the flight period normally associated with local moths. With the assistance of District staff in Labrador a small number of SBW pheromone traps will also be placed in areas forecast to have light damage in 2012. The objective will be to examine the trapping thresholds or number of moths caught in these areas. Zinc Mine Rd. Aerial Overview Survey: An aerial overview survey to detect and map the severity and extent of damage caused by SBW was conducted in Labrador around the Goose Bay area on July 9-10th. Additional flying was also conducted in Labrador from August 14-18th.

Sally’s Cove

Botwood Hwy

Observations from the air and on the ground in 2011 indicate that populations have dramatically decreased in most areas around Goose Bay. This was not unexpected given the forecast from 2010 (Table 5). Other than in a few areas the damage observed was minimal with trees previously damaged showing signs of recovery and producing new foliage (Figure 15). A small area (217 ha) with moderate defoliation was detected near Sheshatshiu. Figure 14. Eastern spruce budworm pheromone trapping results – 2011. Larger areas with M-S defoliation appeared to shift further east along the south shore of Lake Melville in the vicinity of the English River. Here SBW numbers were quite high and defoliation was readily evident. A total of 7846 ha of moderate and 13944 ha of severe defoliation were detected from the air in 2011 Figure 15. Branch with recovery. (Figure 16). This is less than the areas of defoliation mapped in Labrador in 2010 (58011 ha), 2009 (45052 ha), and 2008 (24661 ha). In addition to the smaller area of defoliation in 2011, damage and mortality that occurred in previous years was still very much evident in the Travespine River area. No SBW defoliation was observed or reported on the island in 2011. Fall Egg Mass Survey: Collection of branch samples to determine the number of SBW egg masses has been conducted in Labrador since 2007 (Table 6). In 2011, branch samples were again collected in mid to late October and sent to the lab in Pasadena where trained observers examined the branches for the presence of hatched egg masses. Results indicate that SBW populations will remain active around the Goose Bay area with 17 locations forecast to have no damage, 19 locations forecast to have light damage, 2 locations forecast to have moderate damage (south shore of Lake Melville near the English River; 16 km southeast of Goose Bay (Mud Lake)) and one location forecast to have severe damage (8 km east of Goose Bay) (Figure 17). Although populations are still active, they are certainly much lower than observed in 2009 where 31.4 and 28.6 percent of the plots assessed that year were forecast to have moderate and severe damage. Only 4.8 and 2.4 percent of plots assessed in 2011 are forecast to have moderate and severe damage. Locations in Labrador where SBW populations are forecast to be moderate and severe in 2011 were provided to District staff and no concerns regarding impacts and the need for control were expressed.

11


On the island, the three locations (Sally’s Cove, Zinc Mine Rd., Botwood Hwy.) with the highest trap catches were also assessed for SBW egg masses. The Botwood Hwy location was the only site where SBW egg masses (2 egg masses – light defoliation forecast) were found.

Figure 16. Areas of moderate and severe SBW defoliation mapped around the Goose Bay area in Labrador – 2008 to 2011.

12


Table 6. Provincial summary of spruce budworm egg mass survey results by damage/population categories - 2007 to 2011.

Year 2011 2010 2009 2008 2007

Provincial Area

Number of locations


Island Labrador Total Labrador Labrador Labrador Labrador

3 39 42 50 35 25 18

33.3% 56.4% 54.8% 0.0% 88.6% 60.0% 0.0%

Egg masses/10 sq m of foliage by location in damage thresholds Nil 0

Light 1-107

Moderate 108-258

Severe >258

2 (66.6%) 17 (43.6%) 19 (45.2%) 50 (100%) 4 (11.4%) 10 (40.0%) 18 (100%)

1 (33.3%) 19 (48.7%) 20 (47.6%) 0 10 (28.6%) 15 (60.0%) 0

0 2 (5.1%) 2 (4.8%) 0 11 (31.4%) 0 0

0 1 (2.6%) 1 (2.4%) 0 10 (28.6%) 0 0

Maximum egg masses / 10 sq m

Total Egg Masses

Mean egg masses/ 10 sq m

14 1677 1677 0 1780 90 0

2 2537 2539 0 11688 221 0

0.22 65.1 60.5 0.0 333.9 8.8 0.0

Figure 17. Areas forecast to have SBW defoliation in and around Goose Bay area in Labrador in 2012.

Balsam Fir Sawfly – The balsam fir sawfly (BFS) is another major forest pest that is native to the Province that can cause adverse impacts on our forests. Unlike other defoliators which attack the current-year foliage, the BFS feeds on old foliage and uses the currentyear foliage predominantly for egg laying. Although outbreaks of this pest are frequent, they are usually short-lived lasting only 3-4 years due to the presence of a naturally occurring virus and other natural controls (i.e. predators and parasites). The defoliation caused by BFS reduces diameter growth with recovery to pre-defoliation growth rates taking up to 10-years following moderate to severe feeding. Mortality of host trees may also occur especially in areas where other defoliators are active and feeding on the current-year foliage. The last BFS outbreak occurred on the island from 1991 to 2009. During this outbreak aerial control programs were conducted to mitigate impacts caused by this pest. 13


Pheromone trapping survey: Currently there is no artificial pheromone lure available for detecting and monitoring of BFS populations. A research project to identify and develop a BFS pheromone for population monitoring and field testing is on-going through SERG-I – this may provide another tool for monitoring low density populations of this forest pest in the future. Aerial Overview Survey: One of the primary means for detecting this pest is through observations of damage made by IDCS staff and reports received from DNR District staff, forest industry, and the public. In 2011, damage from BFS was reported by District 7 staff on the Connaigre Peninsula (Figure 18). During the aerial overview survey conducted on the island by IDCS staff in late August, 12937 ha of moderate to severe BFS damage was mapped in scrub forest stands in this area. Small localized pockets of BFS defoliation were also observed from the ground by IDCS staff in west-central portions of the island near the SE border of Gros Morne National Park. Fall Egg Survey: Branch samples were taken from a total of 119 locations to forecast BFS populations for 2012. Collected branch samples were transported to the lab in Pasadena were trained observers recorded the total number of BFS eggs found on 50-cm branch tips (one branch/tree; 5 trees/location) from each location. Forecast results (Table 7; Figure 18) indicate that BFS populations continued to decline, however, damage levels will remain high again and expand slightly in the Connaigre Peninsula area. Again much of the area forecast to have moderate to severe defoliation will be in stands typed as scrub. One forecast Figure 18. Balsam fir sawfly defoliation in 2011 and forecast for 2012. point ca. 40 km north of the Connaigre Peninsula (6 km N of St. Albans) is forecast to have moderate defoliation. This point is within a silvicultural area were thinning operations have been conducted in the past. Defoliation and populations within this silvicultural area will be monitored closely in 2012. In west-central NL, BFS populations will again be active with 7 locations forecast to have light damage and one location north of Bonne Bay Little Pond forecast to have severe defoliation. Table 7. Provincial summary of balsam fir sawfly egg survey results by damage/population categories - 2000 to 2011.

Year 2011

Provincial Area

Number of locations


Total eggs per location (five trees; one 45-cm branch tip/tree) by damage threshold Nil Light Moderate Severe 0 1-100 101-200 >200

Maximum eggs/ location

Total Eggs

Mean eggs/ location

Island Island

119

15.9%

100 (84.0%)

9 (7.6%)

2 (1.7%)

8 (6.7%)

1764

4668

39

2010

123

41.5%

72 (58.5%)

40 (32.5%)

4 (3.3%)

7 (5.7%)

672

4172

34

2009 2008 2007 2006 2005 2004 2003 2002 2001 2000

Island Island Island Island Island Island Island Island Island Island

188 198 222 237 239 209 191 285 291 252

46.3% 83.8% 77.4% 55.3% 54.4% 57.4% 70.7% 62.2% 62.2% 61.1%

101 (53.7%) 32 (16.2%) 50 (22.5%) 106 (44.7%) 109 (45.6%) 89 (42.6%) 56 (29.3%) 151 (53.0%) 110 (37.8%) 98 (38.9%)

75 (39.9%) 134 (67.7%) 136 (61.3%) 87 (36.7%) 70 (29.3%) 77 (36.8%) 93 (48.7%) 94 (33.0%) 115 (39.5%) 59 (23.4%)

4 (2.1%) 13 (6.6%) 14 (6.3%) 13 (5.5%) 18 (7.5%) 10 (4.8%) 23 (12.0%) 17 (6.0%) 15 (5.2%) 26 (10.3%)

8 (4.3%) 19 (9.6%) 22 (9.9%) 31 (13.1%) 42 (17.6%) 33 (15.8%) 19 (9.9%) 23 (8.0%) 51 (17.5%) 69 (27,4%)

672 4339 2080 1778 3210 1435 1949 1042 4936 5212

4957 22556 17500 19365 32936 18297 14701 15734 44847 59010

26 114 79 211 138 88 77 55 154 234

14


Spruce Beetle – The spruce beetle (Dendroctonus rufipennis Kirby) (SPBTL) is one of the most widely distributed bark beetles in North America, ranging from Newfoundland and Labrador to Interior Alaska to southern Arizona. SPBTL is a native pest that attacks mature and overmature spruce with white spruce being the preferred host, but all species of spruce can be attacked and killed. Immature stages of the beetle cause the damage with larvae feeding under the bark eventually girdling the trees and killing them. Outbreaks of spruce beetle have been on the rise in recent years in various jurisdictions. Climate change is thought to be partly responsible with warmer winters increasing the survival of over wintering stages. Aerial Overview Survey: Aerial surveys on the island and in Labrador continued to detect areas of SPBTL damage. Damage detected included yellow trees (those recently attacked), red trees (those recently killed), and older mortality. Damaged trees continue to be found on the island in the Humber River Valley. In Labrador SPBTL damaged trees continue to be found in the Grand Lake road and Mud Lake/Kenemu River areas. In 2005, 10988 ha with severe defoliation and dead trees were mapped. In 2006, this area expanded to 14705 ha. Although very few new areas were detected in 2011, the area of SPBTL damage in Labrador has continued to grow in the last seven years and now covers an area of 41097 ha (Figure 19). Within this area there is now more old mortality (i.e. grey trees and fallen timber) and fewer yellow and red trees. Fortunately much of the area affected is in non-commercial or scrub stands with poor sites.

Figure 19. Areas with damage from spruce beetle in and around Goose Bay area in Labrador - 2006 to 2011.

15


Brown Spruce Longhorn Beetle – The brown spruce longhorn beetle (Tetropium fuscum Fabricius) (BSLB) is an invasive forest insect that was first introduced into Halifax in the late 1980’s. Life-stages found underneath the bark of wood packaging material or pallets stored at a nearby container port are suspected as the source. Adult beetles emerging from these materials dispersed into nearby stands of spruce. In its native range BSLB is a secondary pest, but in Nova Scotia it has attacked healthy spruce of all species. Similar to the native spruce beetle, immature stages of the BSLB feed underneath the bark of host-trees, eventually girdling and killing them. Despite early efforts to eradicate and prevent the spread of this pest, BSLB trapping results (Neville, 2011) from the CFIA indicate that populations of this pest have continued to spread in Nova Scotia over the last six years (Figure 20). In 2011, BSLB adults were trapped for the first time in Kouchibouguac National Park in New Brunswick. Firewood brought in by campers is suspected as the source of this latest find. Figure 20 also provides a map of all the sites (red - positve; black – negative) where trapping was conducted in Atlantic Canada in 2011. For invasive species, identifying high-risk commodities and pathway is extremely important. In the case of BSLB these commodities would include spruce round wood with bark on it; firewood; and wood packaging material. In NL, BSLB traps were placed by CFIA staff at high-risk sites including ports and wood processing facilities. Trapping was conducted at a total of 19 sites (5 traps 2 in the port area and 3 in forested areas (Pippy Park; site of old Salmonier tree nursery; Donovan's Industrial Park); Argentia Port/Industrial Park; Jamestown Lumber (Jamestown); Sexton Lumber Figure 20. Trapping results for Brown Spruce Longhorn Beetle in Atlantic Canada – 2006 to 2011. (Bloomfield), NL Hardware (Clarenville); Paul Garland Forest Products (Tilton); Gander International Airport; Salmonid Interpretation Centre (Grand-Falls - Windsor); Woodale Provincial Tree Nursery (Grand-Falls - Windsor); and 6 traps around the port and at sawmills in the Corner Brook Area. No adult BSLB were caught in traps at any of these sites. Although these results are welcomed, the proximity of positive finds in Atlantic Canada certainly reinforces the need to remain vigilant in NL. Although the movement of certain high-risk commodities is regulated by the CFIA under the Federal Plant Protection Act, add-

16


itional public education efforts in cooperation with other Departments concerned about other invasive alien species should be considered to highlight the risk of introducing BSLB to the Province through the movement of commodities like spruce logs and firewood from sources outside the Province.

Other Insect Pests – A number of other insect pests were detected or reported during the 2011 field season. European Pine Shoot Moth - This insect continues to be a common pest found on planted red pine on the island. Hairy Poplar Sawfly – Reports of localized damage by this pest were reported by the public and confirmed by DNR (IDCS and District) staff in the St. Anthony area. Large numbers of sawfly were evident and balsam poplar trees were severely defoliated. Grasshoppers – Moderate to severe damage on young spruce by grasshoppers was reported by DNR Regional/District staff in a plantation in the Goose Bay area in Labrador. Samples provided to the IDCS by District staff were identified as Melanoplus fasciatus Walker by staff of Agriculture and AgriFood Canada (personal communication, P. Dixon. 2012). Although not common, damage by grasshoppers to seedlings of planted jack pine and red pine was also observed and reported in Manitoba in the 1970’s.

Forest Disease Pests Scleroderris (EU – European Strain) Canker of Pines – The European strain of Scleroderris (EU) (SCLEU) canker is another invasive forest pest. It was detected in NL for the first time in St. John’s in 1979 and is a serious disease of hard pines. It causes branch dieback, stem cankers and tree mortality in both young and mature trees with red pine (rP) being the most susceptible. Other pine species like jack pine, Scots pine, and Austrian pine are less susceptible to SCLEU and may not be killed; however, they can harbour the disease and produce spores capable of infecting other pines. Historical finds of SCLEU on the Avalon Peninsula led to it becoming a quarantine zone under the Federal Plant Protection Act. In 1988, confirmed sites (Bonavista Peninsula; Sunnyside) with SCLEU finds north of the Avalon were sanitized. Temperatures of 0-4°C and wet conditions for periods of 20-days are ideal for short range dispersal and intensification of this disease. SCLEU spores require moisture and are spread through rain splashing and the movement of birds and animals during wet periods. Conversely, the long range movement of this disease is possible through the movement of living infected plant material (i.e. seedlings, trees). For 28 years this quarantine zone and regulations preventing the movement of living materials, the natural barrier of the Avalon Peninsula isthmus, and past sanitation efforts have been successful in limiting the spread of this disease. In 2007, however, a rP plantation in the Berry Hill Pond area ca. 400 km from the quarantine zone, was surprisingly found to have the disease. Evidence appears to suggest that the long range movement of the disease may have occurred through hunting parties who brought infected rP material as firewood from the Avalon. Studies have also shown that this disease remains active on cut branches and cankered stems for up to 2 and 5-years. To address this new introduction work was conducted in 2007 and 2008 to sanitize this site. This involved cutting down all host rP material in portions of the site heavily infected and pruning of lower branches in the remainder of the area in 2007. In 2008, however, it became apparent that the disease was more widespread than originally observed and the remainder of the plantation was cut, the tops and branches were placed in wind rows and the stems of the trees were cut in 4 foot lengths and cross-piled. Repeated attempts to burn this material in the same year, however, were unsuccessful. In 2010, red discoloration of foliage was again observed in another rP area ca. 3¼ km N of the 2007 site. Samples collected that year however, found only a minor disease called red band needle blight. In 2011, however, aerial observations noted a dramatic change in the discoloration observed in this site with pockets of mortality now evident (Figure 21). Additional ground sampling identified characteristic symptoms of damage associated with Scleroderris (EU). Examination of the spores from the picnidia or fruiting structures of the disease by Dr. Gary Warren of the CFS confirmed it was the European strain of this disease. Several weeks later, aerial surveys being conducted also found similar damage in rP planted areas in the White Hills area N of Clarenville. Subsequent ground sampling and examination of these samples by Dr. Gary Warren of the CFS once again confirmed the presence of SCLEU. Staff from the CFIA in St. Johns were contacted by DNR Figure 21. Damage from Scleroderris (EU) canker observed from the air in 2011.

17


and made aware of these finds. Arrangements were also made for DNR IDCS and CFIA staff to meet at these locations where additional samples were collected by the CFIA for lab processing – these again confirmed the presence of SCLEU not only at these two sites, but also a jack pine site in Conne River Pond (personal communication, T. Drover. 2011). To address the threats from this disease a Scleroderris (EU) working group was formed to provide recommendations to the Department on how to address this problem. The working group has representation from DNR (IDCS, Silviculture, Regions/Districts), the CFIA, the CFS, and the Department of Environment and Conservation. Part of the responsibility of this group was to discuss the impacts from this disease. Obviously, indirect impacts can occur as a result of quarantine zones and regulations. This can adversely affect trade and restrict the movement of commodities and materials deemed to pose a significant risk to the spread this disease. Fortunately in NL there are presently no significant indirect impacts as red pine is not used commercially. One concern, however, was related to CFIA’s existing regulations for this disease. Under D-98-02 the only regulated commodities are nursery stock, forest tree seedlings, and pines originating from other countries. Wood/bark chips, cones, seeds, logs, lumber, cut Christmas trees (including branches and other non-propagative parts) of all species including Pinus are exempt. Given the studies showing that this disease can remain active on cut branches and cankered stems for up to 2 and 5-years, the CFIA was asked to review this information to ensure that all high-risk commodities are identified in their regulation to help prevent the spread of this disease. By far the greatest impact identified by the group was the direct impact that this disease can have on red pine on the island. Both indigenous or native red pine and planted red pine are at risk. Work conducted by Bruce Roberts (1985) identified 20 indigenous rP stands of ecological significance. These stands represent an area of ca. 761 ha or 12470 trees. In addition, a significant silvicultural investment has been made in the planting of rP on the island. Silvicultural records indicate that ca. 7.5 million rP were produced and planted during the period 1981 to 2010. Using a planting density of 2400 trees/ha and a cost of $1000/ha this represents an area of ca. 3100 ha and an investment of $3.1 million dollars over a 30-year period. The location and distribution of these indigenous stands in relation to planted rP and jP can be found in Figure 22. This figure also shows the sites where Scleroderris Canker has been found in the past, and the area (Avalon Peninsula) currently regulated by the CFIA.

Figure 22. Maps showing indigenous rP, quarantine zone, planted rP and jP, and new Scleroderris (EU) sites.

18


In Berry Hill Pond ca. 47 ha of rP plantations are currently infected. Planted in 1989, the rP are now 6-7m in height and 15-18cm in dbh. The stands are very dense with the lower limbs providing a suitable environment for the disease. Once the disease moves up the trees (mortality centers) it appears to move across the crowns. This was also observed in the Berry Hill Pond site detected in 2007 and also documented in a large area in Sweden. The micro climate found within the Berry Hill Pond area appears to be extremely favourable for this disease, hence, the rapid build-up and top down infection not normally observed. Subsequent aerial and ground work was conducted to document the distribution and level of infection from this disease. A total of 99 locations were assessed from the ground using a technique developed by Dr. Garren Warren and Dr. Gaston LaFlamme. All locations were positive with varying levels of infection indicating that the disease is now well established and found throughout these planted areas (Figure 23). In White Hills ca. 21 ha of rP plantations are affected and represent four separate areas planted in 1988. The trees are roughly the same height and dbh as those found in Berry Hill, however, portions of these areas have a high percentage of other tree species. Additional ground work was also done in these areas to document the distribution and level of infection observed. Evidence of SCLEU was observed at 51 out of 56 locations (Figure 23), however, unlike the planted areas in Berry Hill there was a considerable amount of damage from the European pine shoot moth - this made damage ratings difficult at this site. In White Hills, the level of infection was not as widespread – although small areas existed with dead trees and discoloured foliage in the mid to upper crown, there were many trees where picnidia of the disease could only be found near the base of old needles on a few lower branches.

Figure 23. Maps showing distribution and level of Scleroderris (EU) infection found at ground locations assessed in Berry Hill Pond and White Hills in 2011.

The Scleroderris (EU) canker working group agreed upon and suggested the following items for dealing with the SCLEU problem. -

The European strain of Scleroderris Canker poses a significant threat to both the indigenous and planted rP on the island.

-

The quarantine zone and associated regulations, natural barrier of the isthmus (on the Avalon Peninsula), and past sanitation efforts have limited the spread of this disease in the past – there’s no reason to suspect this strategy will not work again.

-

That the risk of spread and impacts from this disease warrant conducting sanitation programs at both sites with the priority being White Hills given its closer proximity to populated areas, and other indigenous and planted rP. The Berry Hill Pond site

19


is more isolated and there are fewer pine stands in the vicinity, however, little can be done to control the movement of people and animals in and out of the area. As such it still poses a threat with respect to the potential long range movement of the disease. -

A directed (aerial and ground) SCLEU survey be a priority in 2012 to determine if this disease can be found at a more sites or if it’s distribution is still very limited.

-

If limited, given the difficulty in burning the rP material in Berry Hill Pond, other sanitation methods such as mulching be considered. This method poses less risk with respect to the theft or movement of infected materials off site. Precautions such as steam cleaning of equipment would be needed before any equipment left the site. Other methods to prevent the spread of this disease would also be necessary for those working on site. Beyond providing sanitation, the mulching method would quickly reduce the risk of spread of this disease and make it easier to plant and convert these sites to other productive species.

-

Other considerations with respect to future regulation, management and monitoring of rP were also suggested – they included the following. o o o o

A re-examination of scientific information by CFIA with respect to what commodities pose a risk for spread of this disease. Should pine branches, pine Christmas trees, pine logs be added to items regulated? Greater public education and awareness with respect to the risk of moving high-risk commodities – for example, a guide/pamphlets for hunters, outfitters, campground operators, National Parks etc. A review of the benefits and practicality of pruning lower branches as part of the management prescription for all rP plantings or those close to indigenous rP areas to prevent build-up of this disease in the lower crowns. Assessments of jP and Scot’s pine stands close to indigenous rP areas or plantings to see if Scleroderris is present. If so, these other pine stands could provide a source of inoculum of the disease that can be spread to neighbouring rP stands.

Some of the above items are already on-going or completed thanks to the cooperation received from participants (i.e. CFIA review of scientific information, public education piece in Provincial Hunter and Trappers Guide), while others (e.g. directed SCLEU survey by DNR IDCS) are being planned and will be conducted in 2012. Under federal regulations the CFIA will also impose a prohibition of movement (a 1-km buffer) around the sites found to be positive with SCLEU in 2011. The goal of the prohibition of movement is to prevent the spread of this disease by prohibiting the movement of living pine material from infected to uninfected areas.

Other Disease Pests – A number of other disease pests were detected or reported during the 2011 field season. Red band needle blight – Damage from red band needle blight was also detected in rP plantations where SCLEU was found. Red band needle blight can be an economically important disease of conifers with defoliation causing premature needle loss and reductions in yield. In cases where severe defoliation occurs over consecutive years it may also cause tree death, but typically it is not a tree killer like SCLEU. Spruce Needle Rust – DNR Regional/District staff reported heavy needle rust infection on spruce in the Grand Lake Road area near Goose Bay, Labrador. Reports of heavy needle rust infection in and around Labrador City were also received. The fruiting structures, yellowishorange spores, and discoloured needles associated with this disease give the trees a distinctive off-colour appearance. Even from a distance, this discoloration was evident on trees on hillsides. In addition, the large number of spores present in these areas caused an orange-red residue to be found along the shorelines of water bodies. This would be similar to the yellow film often observed in the water and along shorelines in heavy pollen years. Needle rust was also reported in spruce plantations assessed as part of the high-value survey conducted on the island in 2011. Although needle rust infection can be very high in some years, the rate of infection is usually not high enough in consecutive years to pose a significant threat to the trees.

Assessment of High Value Areas (Plantations and Thinnings) The Province has invested millions of dollars in silviculture with annual expenditures of 11-12 million dollars alone in each of the last 3-4 years. Currently there are approximately 250 000 hectares of high value areas. This represents about 19 to 20% of the 1.3 million hectares of forest considered to be productive and operationally available for harvest on the island. Although aerial overview surveys and to a lesser extent forecast surveys provide some pest monitoring in these high value areas, to date there has been no directed detection survey to monitor forest health (i.e. forest pest incidence and damage) in these areas. In addition, there is no routine or systematic assessments (i.e. 5 or 10-year assessments) made in these areas following their establishment. Given the above, a directed survey in high-value areas was initiated in 2011. The purpose of this survey was to assess forest health within these areas by determining what forest insect and disease pests or abiotic agents were present. Beyond identifying what pests

20


were present, it also identified their relative abundance and damage observed. Given the prevalence of balsam woolly adelgid (Adelges piceae (Ratz.)) (BWA) on balsam fir in the Province, the high-value survey was combined with a survey to conduct additional work to assess the levels of damage found in balsam fir thinnings. BWA damage classes modified from work done by Schooley and Bryant (1978) were used to assess damage into broad classes of light, moderate and severe. The methods used to conduct these assessments are described in Appendix D and are similar to methods employed in the Province of New Brunswick to assess forest pest incidence in high-value areas (Lavigne, 2008) and assess damage from the BWA (Lavigne, 2005). The form and navigational tools used to conduct this combined survey can also be found in Appendix D. During the months of July and August, DNR’s IDCS assessed a total of 97 balsam fir thinnings and 35 plantations (Figure 24). The total number of plantation and thinnings assessed is also summarized by Region, District, and primary tree species (Table 8).

Figure 24. Map showing distribution of plantations and thinnings assessed during 2011 high-value survey.

21


Table 8. Summary of areas assessed during high-value survey by Region, District, silvicultural treatment, and primary tree species.

Region

District

bS

wS

spruce/bF

bF/spruce

bF

Total

9

Thinnings

1

0

2

5

1

9

12

Thinnings

0

0

0

2

5

7

13

Thinnings Thinnings Plantations Totals Thinnings Plantations Totals Thinnings Plantations Totals Thinnings Plantations Totals Thinnings Plantations Totals Thinnings Plantations Totals

0 0 7 7 1 3 4 1 3 4 0 0 0 0 1 1 3 14 17

0 0 0 0 0 1 1 0 0 0 2 8 10 0 4 4 2 13 15

0 0 0 0 0 2 2 0 0 0 0 2 2 0 0 0 2 4 6

0 0 0 0 3 0 3 0 0 0 0 0 0 2 0 2 12 0 12

2 6 0 6 36 0 36 5 0 5 5 0 5 8 0 8 68 0 68

2 6 7 13 40 6 46 6 3 9 7 10 17 10 5 15 87 31 118

Thinnings Thinnings Plantations

0 1 3

0 0 1

1 2 0

3 0 0

0 3 0

4 6 4

Totals

4

0

3

0

3

10

1 3 4 4 17 21

0 1 1 2 13 15

3 0 3 5 5 10

3 0 3 15 0 15

3 0 3 71 0 71

10 4 14 97 35 132

14

15

Western 16

17

18

Western Region Totals 10

Eastern

Primary Tree Species

Silvicultural Treatment

11

Thinnings Plantations Totals Thinnings Plantations Overall Totals

Eastern Region Totals Provincial Total

Where this was the first year for this survey, most of the work completed in 2011 was conducted in the Western Region with bF thinnings and thinnings in general being sampled more often than plantations. A summary of the forest pests detected in these areas indicated that twig attack from BWA, browsing by moose (Alces alces), and damage by the Balsam gall midge (Dasineura balsamicola (Lintner)) were the three most common occurrences on bF (Table 9). Note - totals in Table 9 will not match the totals in Table 8 as multiple pests may have been recorded at a single location). On spruce, the most common pest occurrences were spruce budge midge (Rhabdophaga swainei Felt), needle rust (Chrysomyxa ledi (Alb. & Schwein)), and moose browse. Table 9. Summary of forest pests identified and their incidence in high-value areas assessed on the island in 2011.

Region Eastern

District 10

Silvicultural Treatment Thinning

Tree Species* bF

Number Of Assessments 8

Number with no Pests or Damage 0

22

Number with pests or damage 8

Pest or cause of damage Balsam Woolly Adelgid (BWA) BWA Clubbed Top Moose Moose Snow

Frequency and % of trees affected 1 (6-30%) 1 (>-70%) 2 (6-30%) 1 (6-30%) 2 (1-5%) 1 (6-30%)


Table 9. cont. Region Eastern

Western Western

bS wS

Number Of Assessments 2 1 1 12 3 3

Number with no Pests or Damage 0 0 0 0 2 1

Number with pests or damage 2 1 1 12 1 2

bF

6 5

3 1

3 4

bS

3

0

3

wS Subtotal Summary for Eastern Region 9 Thinning bF bS

1 9 27 6 8

0 1 4 5 0

1 8 23 1 8

14 7 2 7

5 7 2 4

9 0 0 3

2

0

2

9 5 1 6 3

4 5 0 5 1

5 0 1 1 2

bF

3 1 7 52

2 0 3 15

1 1 4 37

bS

2

0

2

wB

3

0

3

wS

5 62 3 4

0 15 0 1

5 47 3 3

1 1 6

1 0 2

0 1 4

District 10

Silvicultural Treatment Plantation

11

Subtotal Plantation

11

Subtotal Thinning

12 13 14

Subtotal Thinning Thinning Plantation

Tree Species* bS wP wS

bF bF bS Pin Cherry

14

Subtotal Thinning

15

Subtotal Plantation

bF bS bF bS wS

15

16

Subtotal Thinning

Subtotal Plantation Thinning

bF bF bS wS

Subtotal

23

Pest or cause of damage Forked Top Blister rust Leader damage

Frequency and % of trees affected 2 (6-30%) 1 (6-30%) 1 (6-30%)

Spruce Bud Midge Moose Spruce Bud Midge

1 (>70%) 1 (6-30%) 1 (31-70%)

BWA Snow Unknown Witches Broom Clubbed Top Spruce Bud Midge Unknown Clubbed Top

1 (31-70%) 1 (1-5%) 1 (1-5%) 1 (1-5%) 1 (31-70%) 1 (>70%) 1 (1-5%) 1 (1-5%)

Moose Gall Aphid Spruce Bud Midge Forked Top Moose Needle rust Unknown Witches Broom

1 (6-30%) 1 (>70%) 2 (31-70%) 1 (>70%) 1 (6-30%) 1 (1-5%) 1 (>70%) 1 (1-5%)

Needle rust Needle rust Unknown Black Knot Black Knot

2 (1-5%) 1 (6-30%) 1 (6-30%) 2 (>70%) 1 (31-70%)

Witches Broom

1 (31-70%)

Moose Unknown Needle rust Unknown

1 (1-5%) 1 (6-30%) 1 (31-70% 1 (6-30%)

BWA BWA Gall Midge Gall Midge Gall Midge Moose Moose Unknown Witches Broom Needle rust Unknown Moose Moose Moose

1 (6-30%) 4 (1-5%) 5 (1-5%) 4 (6-30%) 2 (31-70%) 6 (1-5%) 13 (6-30%) 1 (6-30%) 1 (1-5%) 1 (31-70%) 1 (6-30%) 1 (1-5%) 2 (6-30%) 5 (1-5%)

Moose Moose

3 (1-5%) 1 (1-5%) 1 (6-30%) 1 (31-70%) 1 (1-5%)

Moose


Table 9. cont.

Region Western

District 17

Silvicultural Treatment Plantation

17

Subtotal Thinning

18

Subtotal Plantation

18

Subtotal Thinning

Tree Species* bF wS bF

wS bF bS wS bF bS wS

Subtotal Summary for Western Region

*

Number Of Assessments 2 8 10 9

Number With no Pests or Damage 2 6 8 2

Number with pests or damage 0 2 2 7

1 10 1 1 4 6 11 1 1 13 156

1 3 1 1 4 6 9 1 1 11 74

0 7 0 0 0 0 2 0 0 2 82

Pest or cause of damage Moose

Frequency and % of trees affected 2 (6-30%)

Gall Midge Gall Midge Moose Moose WM Tussock Moth -

1 (6-30%) 1 (31-70%) 3 (6-30%) 1 (31-70%) 1 (31-70%) -

Unknown -

2 (1-5%) -

bF = balsam fir; bS = black spruce; wS = white spruce

The larger proportion of bF thinnings assessed as part of the high-value survey also provided a good opportunity to assess the levels of BWA damage found. BWA damage assessments were conducted in 91 of the 97 thinnings. A total of 4684 bF trees were assessed and categorized into damage classes The number and percentage of trees and locations with Nil, Light, Moderate, and Severe damage in each District are summarized in Table 10. Figure 25 also shows the distribution of the locations assessed for BWA and their overall damage ratings with Districts 11, 12 and 14 having a greater number of locations with an overall rating of moderate or higher damage. In contrast, Districts 9, 10, 15, and 16 had thinnings with low or no evidence of damage. The lack of any reports of BWA damage in thinnings assessed in Districts 17 and 18 (Figure 24, Table 9), indicates that BWA is not very active on the northern peninsula. Table 10. Summary of BWA damage observed in bF thinnings assessed during high-value survey in 2011. Region

District

Western

9 12 13 14 15 16

Eastern

10 11

Overall Totals

Damage ratings for trees pooled by District Light Moderat Severe Dead e 298 52 0 2 0 (84.7%) (14.8%) (0.5%) 134 182 50 16 5 (34.6%) (47.0%) (12.9%) (4.1%) (1.3%) 75 50 28 18 0 (43.9%) (29.2%) (16.4%) (10.5%) 188 135 93 35 4 (41.3%) (29.7%) (20.4%) (7.7%) (0.9%) 2269 11 1 0 0 (99.5%) (0.46%) (0.04%) 428 28 4 0 0 (93.0%) (6.1%) (0.9%) 108 17 9 1 0 (80.0%) (12.6%) (6.7%) (0.7%) 224 115 71 33 0 (50.6%) (26.0%) (16.0%) (7.4%) 3724 590 256 105 9 Nil

Total Trees 352 387 171 455 2281

Overall (weighted) Damage Rating by Location Nil Light Moderate Severe Dead 3 (42.9%) 0 1 (33.3%) 0

135

39 (86.7%) 5 (55.6%) 0

443

0

4684

48

460

4 (57.1%) 3 (50.0%) 0 4 (36.4%) 6 (13.3%) 4 (44.4%) 2 (100.0%) 5 (62.5%) 28

Total Locations

0

0

0

7

3 (50.0%) 2 (66.7%) 6 (54.5%) 0

0

0

6

0

0

3

1 (9.1%) 0

0

11

0

45

0

0

0

9

0

0

0

2

3 (37.5%) 14

0

0

8

1

0

91

Where moose browse was one of the more common damaging agents found, the locations and percentage of trees with browse were also examined (Figure 26). Moose browse was recorded in Districts 9, 10, 11, 15 and 16. In contrast, no incidence of moose browse was recorded in the high-value areas assessed in Districts 12, 13 and 14.

24


Figure 25. Map showing overall BWA damage rating determined from assessments of bF trees in thinnings sampled as part of the 2011 high-value survey.

25


Figure 26. Map showing locations and percentage of trees with moose browse recorded during 2011 high-value survey.

In 2012, work in high-value silvicultural areas will be continued to monitor forest pests. Efforts will be made to assess plantations and thinnings in areas not assessed in 2011, while maintaining a level of monitoring across the Province. The IDCS would also be interested in providing insect and disease recognition training to Regional/District staff to assist with general surveillance and assessment of high value areas in the future.

26


Research The Department continued to participate in research projects in 2011 through the Spray Efficacy Research Group – International (SERGI). SERG-I brings together forest pest managers, regulators, research agencies, pesticide suppliers, and others interested in forest pest management. SERG-I primary goal is to improve application technology, pest management methods, and the use of pest control products in an integrated forest pest management approach. It facilitates the efficient use of resources for collaborative research to help meet the needs and priorities of pest managers. It also provides a means for members to work cooperatively on research projects through the sharing of expertise, and financial and in-kind resources to achieve common goals in the areas of spray efficacy and integrated pest management. A number of projects (Table 11) of interest to the Province were funded through SERG-I with financial administration provided by Forest Protection Limited (FPL) in New Brunswick for 4 of the 5 projects; and Grenfell Memorial University providing financial administration for the remaining project. Table 11. Research projects partially funded through the Spray Efficacy Research Group – International in 2011. Research NL Funding Project Provided Establishing a Wind Tunnel Facility and Aerial Application Spray Research Program $3000 Identification of Sex Pheromone for Monitoring Balsam Fir Sawfly $2000 Moving Towards Operational Pheromone Application for Spruce Budworm Mating $2000 Disruption Developing and testing of user-friendly spray formulations for the application of semio$3000 chemicals to control forest insect pests Managing Hemlock Looper in a changing Environment $50000 TOTAL $60000

Financial Adminstration FPL FPL FPL FPL Grenfell

Given the impact of hemlock looper on the forests of NL, the most significant research contribution has been towards a research project being conducted by Dr. Lucie Royer of the Canadian Forest Service. This is a five-year project to determine and evaluate the major ecological factors affecting the population dynamics of HL with the overall purpose of providing critical information required to predict HL phenologies and population densities in a changing environment. This information will be extremely valuable in trying to manage and mitigate the impacts from this major forest pest in the future. A summary of the work conducted through these research projects is provided in Appendix E. In addition, the department continues to contribute to forest pest research and forest pest management in general through its involvement with the National Forest Strategy (NFPS), in particular it’s involvement with the NFPS Steering Committee, NFPS Working Group and assistance with other NFPS projects (i.e. reports, workshops, provision of data). Identifying research priorities and participating in research initiatives continues to be an important component in providing the information and tools needed to protect our forests using an integrated forest pest management approach.

27


References Clarke, L. 1990.

Forest Insect and Disease Survey Work Outline Field Season 1990. Forestry Canada, Newfoundland & Labrador Region. Page 28.

Dixon, P. 2011. Personal communication. Agriculture and Agri-Food Canada – St. John’s, NL. Drover, T., 2011. Personal communications. Canadian Food Inspection Agency – St. John’s, NL. Hébert, C. 2008. Outbreak history, impact and monitoring of the hemlock looper. Pest forum presentation. Dec. 2, 2008. Hartling, L. et al. 1991. Hemlock Looper in New Brunswick Notes on Biology and Survey Methods. New Brunswick Department of Natural Resources – Forest Pest Management Section, in-house report, pp. 25. Lavigne, D. 2008. New Brunswick Regional Forest Pest Detection Program. New Brunswick Department of Natural Resources – Forest Pest Management Section, in-house report, pp. 40. Lavigne, D. 2005. Balsam Woolly Adelgid Work conducted by the New Brunswick Department of Natural Resources in New Brunswick – 2002 to 2004, New Brunswick Department of Natural Resources – Forest Pest Management Section, in-house report, pp. 23. Neville, R., 2011. Brown Spruce Longhorn Beetle (Tetropium fuscum) Survey Results. Canadian Food Inspection Agency – Halifax. Presentation to AACIFP, Dec. 6, 2011. Roberts, B. A. 1985. Distribution and extent of Pinus resinosa Ait in Newfoundland. Rhodora, Vol. 87: p. 341-356. Royer, L., 2011. Personal communications. Canadian Forest Service – Laurentian Forestry Centre. Schooley, H.O. and D.G. Bryant, 1978. The Balsam Woolly Aphid in Newfoundland. Environment Canada. Forestry Service. ISSN 0704-7657: 27-30.

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APPENDICES

29


30


Appendix A – Comparison of Larval Indices using Ocular versus Head Capsule Measurements The larval stage of many insect species including HL, SBW, and other softwood and hardwood defoliators is the stage of most interest to pest managers. The larvae themselves go through various stages as they molt and shed their exoskeleton and become larger. In Newfoundland and Labrador the eastern hemlock looper has four stages and occasionally a fifth. To monitor the development of the larval stage, biologists/entomologists refer to these stages as larval instars. Typically, the larval instar of various insect pests is determined through the measurement of the insects headcapsule width, however, IDCS within the NLDNR have been assessing instars visually (ocular method) based on the length/size of the insect. For HL in Newfoundland and Labrador these headcapsule widths have been defined by Dr. Lucie Royer of the Canadian Forest Service as follows. Larval Mean HC Mean HC SEM length SEM width Instar Length (mm) Width (mm) 1 0.402 0.002 0.425 0.002 2 0.639 0.008 0.667 0.007 3 1.051 0.021 1.086 0.021 4 1.423 0.018 1.508 0.016 5 1.960 0.036 2.085 0.092

Colour dark brown dark brown with lighter areas dark brown to black with conspicuous irregular whitish areas amount of light colouring on the head has increased considerably

These mean headcapsule widths and the standard errors of the mean were used to generate headcapsule width ranges for each instar. A dissecting microscope with a scaled eye piece was then calibrated to these ranges using a scaled micrometer. This resulted in the following scaled eye piece ranges for each instar. Larval Instar 1 2 3 4 5

Head capsule widths (mm) 0.423 to 0.427 0.660 to 0.674 1.065 to 1.107 1.492 to 1.524 1.993 to 2.177

Reticule Range at 50X 2.1 to 2.2 3.3 to 3.4 5.4 to 5.7 7.6 to 7.7 10.1 to 10.3

The larval index or indices is an important measure as it is used to determine when treatment blocks are biologically ready for treatment according to the label requirements of the product being used. To control HL populations the pesticide label for B.t.k. recommends that blocks be treated when peak 2nd instar or a larval index of 2.0 is reached. Given the importance associated with the assessment of larval development, a test was conducted to compare the visual estimation of larval instars to the assessment of larval instars using the above defined head capsule ranges. Where peak 2nd instar is used for the timing of treatments, this comparison was limited to the ability of field staff to accurately identify 1st, 2nd, and 3rd instar larvae. On July 14th and 20th, visual assessments of a total of 254 larvae were made to determine the larval development in block 106. All larvae assessed were collected and placed in small vials with 80% ethyl alcohol. The larval instar of each of these insects was subsequently determined using the defined head capsule ranges and comparisons made using the following crosstablulation. Instars based on Headcapsule Widths 1 2 3 Column Totals

Instars based on Visual Method 1 2 91 (35.8%) 4 ( 1.6%) 34 (13.4%) 108 (42.5%) 1 ( 0.4%) 3 ( 1.2%) 126 (49.6%) 115 (45.3%)

Row Totals

3 0 (0.0%) 0 (0.0%) 13 (5.1%) 13 (5.1%)

95 (37.4%) 142 (55.9%) 17 ( 6.7%) 254 (100%)

Using the headcapsule widths a total of 95 (37.4%), 142 (55.9%) and 17 (6.7%) first, second and third instar larvae were collected, respectively. In contrast, the visual method identified a total of 126 (49.6%) first, 115 (45.3%) second, and 13 (5.1%) third instar larvae. Overall, there was 83.4% agreement; however, 15% and 1.6% of the time the visual method underestimated and overestimated the actual larval instar. Examining only the second instars, the visual method misidentified 34 (23.9%) out of 142 larvae as first instars. Based on observations made during the headcapsule measurements, these misidentified larvae had molted to the next instar, however, their body lengths were still small. The same was true for four third instar larvae misidentified as first and second instars.

31


Given the occurrence of the above, a regression analysis was conducted to compare the larval index or indices calculated using the headcapsule instar results versus those made using the visual method. When calculating larval development for a given block, larval instars are used in the following formula to determine the larval index or indices (LI). LI may also be referred to as average instar (AI). Larval index = (number of 1st instar x 1)+(number of 2nd instar x 2)+(number of 3rd instar x 3)+(number of 4th instar x 4) Total number of larvae

AI Headcap

Fifteen pairs of larval indices were generated using visual assessments of larval instar for larvae collected from the mid-crown and lower crown branch samples taken from three marked trees and taken from three beat trees. These were plotted against indices generated using headcap widths to 2.6 determine the actual instars. Not surprisingly there was a 2.4 strong correlation between the LI or AI for the visual method 2.2 and the actual LI determined using headcap measure2 ments. The regression line, however, indicates that the 1.8 visual method consistently provided a slightly lower LI. 1.6 y = 0.9072x + 0.2754 2 Once again, this is related to R = 0.8254 1.4 the visual method underestimating or misidentifying 1.2 the actual larval instar - for 2nd and 3rd instar larvae this 1 occurred 23.9% and 23.5% of 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 the time, respectively. AI Ocular

Operationally, this may result in blocks being opened somewhat later - this could potentially have an impact in a year with a large number of treatment blocks and poor or limited spray weather. Although the headcap method is more accurate for assessing larval instars, the ocular or visual method does provide for much more rapid assessment of insect development. Given the results of this comparison it may be possible to improve the assessment of larval instars using the visual method by ensuring observers pay closer attention to not only the size of the insect, but also the width of the headcaps. A visual tool developed by Dr. Lucie Royer for rapid assessment of larval instars showing headcap sizes for each instar (shown below) can assist in the latter.

32


Appendix B – Comparison of tree beating versus branch sampling methods for determining larval development; and pre and post-spray results This section provides an overview of work conducted in 2011 to compare tree beating versus branch sampling methods for determining larval development and pre and post-spray results. DNR IDCS staff have typically used a tree beating method to make these assessments in the past. This involves selecting a stand or plot – within this area three different trees are selected each time sampling is conducted. A 6x7ft tarp is placed at the base of a tree and two pole lengths are used conduct three beats or sweeps down one side of each sample tree. Larvae dislodged from mid to lower crown branches found on the tarp are assessed to determine the larval instar of each and the total number of larvae on the tarp counted. The same process is repeated for all three trees. The total number of larvae found provides a population measure before and after treatment. Disadvantages associated with this method include not be able to conduct sampling in wet weather as the larvae won’t dislodge from the tree, difficulty in sampling in windy conditions (i.e. larvae are blown away from tarp); the population counts are influenced by between tree variability (i.e. a different set of three trees taken each time), and large numbers of larvae must be counted especially when populations are high.

Avgerage # of Larvae

In contrast, a branch sampling method was employed utilizing three marked trees in the plot – the same three trees were used for each sample. Using pole pruners 100 cm mid-crown and lower crown branches were carefully collected from each tree to avoid dislodging larvae. Branches were dropped to a tarp, and the larvae removed by beating the branch on the tarp or physically removing the larvae from the branch. The larvae were subsequently assessed to determine their larval instar and counts made to provide population 35 Avg. # of Larvae Avg. # of Larvae measures before and after treatment. It was hoped Beats Branches that this method would reduce the total number of 30 29 larvae that had to be examined. This was indeed the case as shown in the figure to the right. In addition, 25 it was hoped that the variability in population counts associated with using different sets of trees would 20 also be reduced. 16

15

Once sampling began it became apparent that this method could also be employed even in damp 10 10 conditions when the foliage had some moisture. 8 One disadvantage of this method was additional 5 4 4 3 3 care had to be taken in cutting the branches to avoid 2 2 1 1 dislodging larvae. In some cases the cutter head of 0 the pole pruners could not hold the branches for the 1 2 3 4 5 time needed to manoeuvre it into position to drop it to the tarp. This can possibly be rectified in the future by making changes to the existing holders.

Pre and Post-spray Results Where pre and post-spray population counts were available for the two methods, a tabular comparison was made between the overall mortality observed. Percent mortality was calculated using the following formula. ((Pre-spray–Post-spray)/Pre-spray)*100.

7

7 5

7 6

6 3

2 6

7

8

9

10

11

4

3.5

3 AI Branches

Larval Development A regression analysis was conducted to look at the correlation between the larval indices or average instar calculated using the two methods. The two methods were highly correlated with almost a one to one relationship indicating that there is little to no difference in the larval development found using either method.

15 13

2.5

2 y = 1.0594x - 0.1378 2

1.5

R = 0.8976

1 1

1.5

2

2.5 AI Beats

33

3

3.5

4


Results indicated that % mortality was within +/- 10% in two out of the four blocks where both methods were used to assess larval populations. The two remaining block, however, had % mortality levels that differed by ca. 20%. The sampling of different sets of three trees using the beating method could possibly have contributed to these differences – especially where hemlock looper populations can be very spotty and differ considerably between trees in the same plot. With the branch sampling method there is only within tree variability.

Treatment Block 103 104 106 107

Pre-spray Avg. no. Larvae/Tree (Beat Method) 7.7 28.7 34.3 16.3

Pre-spray Avg. no. Larvae/Tree (Branch Method) 6.3 9.3 22.7 15.7

Final Post-spray Avg. no. Larvae/Tree (Beat Method) 4 13 1.7 2

34

Final Post-spray Avg. no. Larvae/Tree (Branch Method) 2 5.7 1.7 0.3

Percent Mortality (Beat Method) 48.1% 54.7% 95.0% 87.7%

Percent Mortality (Branch Method) 68.3% 38.7% 92.5% 98.1%


Appendix C - Comparison of eastern hemlock looper forecast results using different branch lengths and an alternate rinsing method Sampling of branch samples to forecast hemlock looper populations has been conducted in the Province of NL for many years. Sampling was initially conducted by the Forest Insect and Disease Section (FIDS) of the Canadian Forest Service. Instructions provided to FIDS rangers indicated that whole branches were to be collected (Clarke, 1990). These were subsequently processed in a lab using a washing method to dislodge and extract the eggs from the branches. The total number of healthy eggs found on three branches at a location was then correlated to subsequent defoliation to provide thresholds of predicted defoliation. These same methods and thresholds were adopted by DNR’s IDCS in 1974 when it assumed responsibility for insect and disease monitoring and control activities in the Province and no work has been done since to examine or improve these methods. The use of a whole branch was thought to be necessary given the egg laying behaviour of this insect - groups of one to three eggs are laid in various locations such as the forest floor, the stems of trees, under lichens, and tree branches. Whole branches were sampled as they had more suitable egg laying sites (i.e. lichen) further back on the branch. While this sampling method and the associated thresholds appear to have worked well in NL it does require the sampling and processing of large and different sized branches. Other jurisdictions in eastern Canada also use a branch sampling method for forecasting populations, however, all have adopted a standardized branch length. One hundred mid to lower crown branch tips are used in both New Brunswick (Hartling et al., 1991) and Quebec (Hébert, 2008). In 2011, whole branches were again used for the hemlock looper egg survey; however, the numbers of eggs found on different portions of the branch were recorded. In addition, a rinsing procedure not previously employed as part of the wash method was added to see if any additional eggs could be removed. A small test was also conducted to compare the percentage of eggs recovered from branches using a 2% solution of Javex in 20 litres of water (volume for conventional method) versus one using a 2% solution of Javex in 10 litres. Number of eggs found on different portions of branch with and without added rinse Given the collapse in HL populations in 2011, branches from the regular fall egg survey could not be used for this comparison. To conduct this comparison additional sampling was conducted at a location forecast to have moderate populations - a total of 99 trees were sampled. To determine the number of eggs found on different portions of the branch, branch samples were cut into two portions – the 100 cm branch tip and the remainder. These branch portions were processed separately and the number of eggs found on each portion recorded. The 100 cm branch tip was also processed to separate the number of eggs found using the conventional wash method versus one with a rinsing procedure added. The conventional method involves cutting and soaking a branch in a 2% solution of Javex for 45 minutes, stirring every 10-15 minutes, dipping and discarding the branch, putting the remaining solution through two sieves to separate larger materials (20 mesh - 850 um) from finer materials and capture the HL eggs in the bottom sieve (40 mesh - 425 um), and counting the number of eggs under a dissecting microscope. For the rinse procedure instead of discarding the branch material after dipping, it was placed in the sieves and rinsed with water to see if any additional eggs could be removed. The number of eggs found on the 100cm tip, the number of eggs found on the remaining portion of the branch, and the number eggs found after rinsing were recorded for each branch. The total number of eggs for each branch was the sum of these values. The percentages of eggs found on different portions of the branch and by rinsing were then calculated for each branch. The frequency and percentage of branches falling into different ranges corresponding to the total % of eggs found was summarized in the following table. Thirteen branches with no eggs are excluded from this summary. Ranges corresponding to Total % of Eggs Found 0 1-10 11-20 21-30 31-40 41-50 51-60 61-70 71-80 81-90 91-100

100 cm Branch Tip 22 (25.6%) 2 (2.3%) 3 (3.5%) 4 (4.7%) 4 (4.7%) 13 (15.1%) 9 (10.5%) 7 (8.1%) 4 (4.7%) 1 (1.2%) 17 (19.8%)

Portion >100cm 31 (36.0%) 1 (1.2%) 4 (4.7%) 7 (8.1%) 9 (10.5%) 8 (9.3%) 5 (5.8%) 6 (7.0%) 1 (1.2%) 2 (2.3%) 12 (14.0%)

35

From Additional Rinse 43 (50.0%) 4 (4.7%) 12 (14.0%) 5 (5.8%) 10 (11.6%) 6 (7.0%) 1 (1.2%) 1 (1.2%) 1 (1.2%) 0 (0.0%) 3 (3.5%)

100 cm Branch Tip Plus Additional Rinse 12 (14.0%) 0 (0.0%) 2 (2.3%) 1 (1.2%) 8 (9.3%) 9 (10.5%) 6 (7.0%) 8 (9.3%) 4 (4.7%) 5 (5.8%) 31 (36.0%)


Although 36% of the time no additional eggs were found on the portion of the branch>100cm, additional eggs were certainly found in the remaining branches. Interestingly, the rinsing procedure that was added as a test also found more eggs 50% of the time. Twenty-five percent of the time the 100 cm branch tip found no eggs when eggs were found either on the remainder of the branch and/or with the additional rinse. When egg counts from the 100 cm branch tip were combined with egg counts from the rinse this was reduced to 14%. Despite this ca. 25% of the time the portion of the branch >100cm provided 31 to 60% of the total eggs. To see how this affected the actual forecast as defined by the historical thresholds, a crosstabulation comparing total eggs for the 100cm branch plus eggs from the rinse was compared to total egg for the whole branch (i.e.100cm branch tip plus the eggs from the portion of the branch >100cm). Forecast – (eggs on 100cm tip + eggs from rinse) 0 Trace (1-2) Light (3-9) Moderate (10-29) Severe (30+)

0 13 (13.1%) 2 (2.0%) 1 (1.0%)

Forecast – Whole Branch (eggs on 100cm tip + remainder of branch) Trace (1-2) Light (3-9) Moderate (10-29) 9 (9.1%) 3 (3.0%) 28 (28.3%) 4 (4.0%) 3 (3.0%) 23 (23.2%) 5 (5.1%) 2 (2.0%) 6 (6.1%)

Severe (30+)

Seventy-one percent of the time the forecast using the 100cm branch tip combined with the additional rinse provided the same forecast as the whole branch. Eighteen and three percent of the time the forecast increased by one and two categories, respectively. In eight percent of the cases the forecast from the whole branch was lower than the forecast using the 100cm branch tip in combination with the rinse. Although these results are interesting they must be used with caution given the limited number of samples and limited range of forecast values in the dataset. There were no branches with a severe egg count and only a limited number of branches had a moderate forecast. These results certainly warrant further investigation – over time assessments of egg counts on different branch lengths compared to subsequent defoliation should allow new population/defoliation thresholds to be determined on a standardized branch length. For the time being, the length of the portion of branch >100cm ranged from 0 to 111 cm or a mean of 55 cm. In the interim, until the above assessments can be done, a whole branch no greater than 150cm in length (and no less than 50 cm according to original sampling protocols) should be appropriate for forecasting HL egg densities.

% Extraction

Egg extraction rates using 20 versus 10 litres of solution 100 The lab process used to extract or remove larvae from branch 86.3 79 samples typically uses a 25 litre pail with 20 litres of solution. This 80 bucket with solution weighs approximately 20 kg or 44 lbs. Although duties within the lab are rotated, lifting these buckets is physically 60 challenging and must be done with care to avoid injury. Using the same 99 branches, 50 branches were processed as described above using 20 litres of water with 2% Javex. Forty-nine branches were 40 processed as described above using an 18 litre pail with 10 litres of water with 2% Javex. The numbers of eggs extracted from branches, 20 (excluding those removed through rinsing) were determined and means and standard errors calculated for washes done using the 0 different quantities of solution. No statistical differences in egg 10 Litre 20 Litre extraction rates were observed. This suggests that processing of samples in the future can be done with a smaller volume of water without any adverse affect on extraction rates. This would reduce the weight of the buckets by half for staff processing samples in the lab. Depending on the volume of branch material in a sample, from time to time the use of more than one18 litre bucket for processing of a branch sample may be required.

36


Appendix D - Sampling forms and methods used for assessment of high-value areas The overall objective of annual assessments of high-value areas is to record the presence or absence of forest pests and/or damage at a subset of representative plantations and thinnings. Digital silvicultural information for thinnings and plantations along with digital base map layers (roads; rivers, lakes, ponds; wetland; power lines etc) from DNR’s GIS layers were used in ESRI’s ® ArcMap to generate a 1:150,000 mapbook. Thinnings and planted areas by tree species were identified within this mapbook and used by crews to identify and navigate to high-value areas to be assessed.

37


These same Provincial GIS layers were also converted into a Garmin image (img) format using GPS MapEdit and cgpsmapper software and loaded on to Garmin GPS Map62s devices. These GPS units could be used to not only navigate to these high-value areas, but used to navigate within them with stand boundaries and the position of the user shown in the window. Forest pest detection resources including reference books, and a copy of a CD produced by the Fundy Model Forest on Detection and Recognition of Forest Pest were provided to staff. The latter uses forest detection and recognition techniques similar to those formerly used by Forest Insect and Disease staff of the CFS. For identification a four-step process was utilized that looks at what tree species is being affected, the part of the tree being affected, the causal agents (insect, disease, abiotic) observed, and the collection of a specimen with documentation if the causal agent is still unknown. This same identification process was utilized while conducting assessments using a walk-thru methodology. Essentially field staff would look at the shape of stand for the high-value area and a route of travel with two transects and a dog leg used to walk through the area. While walking these transects field staff looked for pests and/or pest damage on primary tree species (i.e. tree species representing >30% of the stand composition) and then provided a qualitative assessment of the pests or pest damage found, % of tree affected, distribution of the pest, and approximate size of the area affected along with specific information on the location assessed on the field form (see page 39). When a pest could not be identified a sample was collected and returned to headquarters. In addition to conducting general surveillance of forest pests in these high value areas, a specific survey to look at BWA damage was conducted simultaneously. The selection of the thinnings assessed was completely random as was the selection of the bF trees in these areas. Depending on the length of the transects field staff would stop every 5 or 10 paces and select the closest bF tree with the aim of assessing ca. 50 to 75 trees in each thinning. BWA damage was classified using modified (broader) damage classes from those originally described by Schooley and Bryant (1978) – see pages 40 to 42. These damage classes were originally modified by staff of the New Brunswick Department of Natural Resources – Forest Pest Management Section for assessments of BWA damage in that Province. Damage class values are assigned to both the upper and lower halves of the tree and averaged into 5-classes (i.e. no damage, light, moderate, and severe damage and dead trees) to estimate BWA damage at the tree level. This provides information not only on the presence or absence of this pest, but also the % of trees found in each damage class. This information was also recorded on the highvalue sampling form. A weighted average was subsequently used to calculate an overall BWA damage rating for the stand.

38


39


BWA Damage Classes (modified from Schooley and Bryant, 1978) Class

Description

Nil

Normal branch angle;

Numerical Code 1

no gouting or visible symptoms of attack.

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Light

Abnormal branch angle (drooping foliage) and node swelling/gout distinct; no or limited stunting or distortion of twigs.

2

40

Forest Insect & Disease Control and Monitoring Activities in Newfoundland and Labrador in 2011 and Outlook for 2012 Class

Description

Numerical Code

Moderate

Distortion and stunting of twigs prominent; branch tips inhibited, swollen and thinly foliated with some branch tips bare.

3

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Severe Branch tips inhibited, 4 swollen and thinly foliated with many branch tips bare.

41

Forest Insect & Disease Control and Monitoring Activities in Newfoundland and Labrador in 2011 and Outlook for 2012 Class

Description

Numerical Code

Dead

Severe gouting and inhibition wih no living foliage in upper crown or lower crown or entire tree.

5

Calculation of Tree Damage Average Damage to Tree (X) = (Damage Code Upper Crown + Damage Code Lower Crown) / 2 Range of mean numerical code

Average Damage to Tree

X=1 X > 1 and ≤ 2 X > 2 and ≤ 3 X > 3 and ≤ 4 X>5

No damage Light damage Moderate damage Severe damage Dead tree

42


Appendix E - Research project updates Abstracts for Research Projects Related to: Establishing a Wind Tunnel Facility and Aerial Application Spray Research Program

43


Abstract for Identification of sex pheromone for monitoring balsam fir sawfly

44


Abstract for developing and testing of user-friendly spray formulations for the application of semiochemicals to control forest insect pests

Progress Report – Managing hemlock looper in a changing environment

45


46


47


48


49


50


51


52


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