Final Report - Manitoba Livestock Manure Management Initiative

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Rural Municipalities in Manitoba

by Petra Loro, Mehdi Arzandeh, Derek Brewin, Wolé Akinremi, Collin Gyles and Dupe Ige

May 30, 2013

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Table of Contents EXECUTIVE SUMMARY ....................................................................................................................... 1 BACKGROUND ........................................................................................................................................ 2 NUTRIENT USE IN CROP PRODUCTION ........................................................................................................2 SOIL P BUDGETS ..................................................................................................................................................3 MANAGEMENT OPTIONS TO IMPROVE P BALANCE ..................................................................................4 Feed Management to Reduce Manure P .............................................................................................. 4 Crop Management to Maximize P Removal........................................................................................ 6 Transport of Manure P to a Larger Land Base .................................................................................. 8 Manure Treatment to Concentrate P ....................................................................................................... 8 OBJECTIVE OF THE REPORT .......................................................................................................... 8 METHODS .................................................................................................................................................. 9 CALCULATION OF P INPUTS ........................................................................................................................... 10 1. Animal Manure .........................................................................................................................................10 2. Synthetic Fertilizer ..................................................................................................................................11 3. Seed ................................................................................................................................................................12 4. Atmospheric Deposition ......................................................................................................................12 5. Municipal Wastewater and Biosolids ..........................................................................................13 CALCULATION OF P REMOVALS ................................................................................................................... 14 A. Harvested Plant Material ....................................................................................................................14 B. Cattle Grazing on Pasture .................................................................................................................14 C. Residue Removal or Burning...........................................................................................................15 D. Runoff.............................................................................................................................................................15 E. Wind Erosion .............................................................................................................................................15 RESULTS ................................................................................................................................................ 16 Table 5: P Inputs, Removals and Budgets by RM using 2011 Pig and Cattle Inventories ..............................................................................................................................................................18 Map 1. Soil P budget estimates by RM for agro-Manitoba.....................................................21 Map 2. Soil P budgets (excluding synthetic fertilizer)by RM for agro-Manitoba........22 CONCLUSIONS..................................................................................................................................... 23 ACKNOWLEDGMENTS ..................................................................................................................... 24 APPENDIX .............................................................................................................................................. 25 Table A.1. Phosphorus Contributions from Livestock in the RM of Arthur .....................25 Table A.2. Phosphorus Contributions from Seed for RM of Arthur .....................................26 Table A.3 Phosphorus Removals and P Budget for RM of Arthur ......................................27 REFERENCES AND ADDITIONAL READING ........................................................................... 28

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EXECUTIVE SUMMARY This report estimates soil phosphorus (P) budgets for each Rural Municipality (RM) in agro-Manitoba with a focus on animal inventories, nutrient excretion and crop production.

Original soil P budget estimates were made by Gyles (2009) using 2006 crop and livestock inventory data from Statistics Canada. Significant reductions in cattle and pig populations have occurred in Manitoba since 2006. Therefore, revised estimates have been recalculated using 2011 pig and cattle numbers.

Of the 78 RMs assessed, the revised budgets demonstrated that most RMs in southern agro-Manitoba are in P balance. In 15 RMs, mostly in the northern half of agro-Manitoba, more P is being removed from the soil than is being replaced with synthetic fertilizer and manure. There are only 9 municipalities that have a surplus of P. Seven of these could achieve P balance by replacing synthetic fertilizer inputs with manure. Two municipalities in Manitoba, specifically Hanover and La Broquerie, have a significant P surplus due to livestock alone.

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BACKGROUND Nutrient Use in Crop Production Nitrogen (N) and phosphorus (P) have been identified as the most limiting nutrients for crop production in Manitoba. To optimize crop yields, these two elements must be supplied either as synthetic fertilizer or as an organic amendment such as livestock manure.

Livestock manure is an important source of nutrients and can replace synthetic fertilizer requirements. The beneficial use of manure in crop production has been recognized since the early centuries when farmers would apply animal dung to their land to boost crop yields. In addition to improving soil fertility, manure encourages soil microbial activity and increases soil organic matter which subsequently improves soil structure, water infiltration and water holding capacity, increases cation exchange capacity and reduces wind and water erosion.

There is increasing concern about the environmental impact of manure application, particularly in areas of high livestock density where the land base is limited. Manure is typically applied based on the N requirements of the crop. Generally, the N:P ratio of manure is lower than the N:P ratio required by crops. Thus, when manure is applied based on crop N requirements, P is applied in excess of what is removed by the crop. The over-application of P is exacerbated by the loss of manure N through ammonia volatilization which further reduces the N:P ratio of the manure. Applications of P in excess of crop requirements results in build-up of soil P which increases the risk of P transport to water bodies through runoff, erosion and leaching (Sharpley et al.,1994; Lennox et al., 1997). Phosphorus in surface water accelerates eutrophication, increases plant and algae growth and can seriously degrade surface water quality.

Several methods are being explored to improve the N:P ratio of manure in order 2

to reduce the accumulation of P in soil when manure is land applied based on N. These methods include modifications to animal diets to reduce the amount of P that is excreted in the manure, minimizing volatilization losses of N during storage and land application as well as manure treatment technologies such as solid-liquid separation. Solid-liquid separation of manure concentrates the P in the solid fraction so that it can be transported more economically to lands that are further away and have lower soil test P. Solid-liquid separation systems are expensive to purchase, install and operate and may not be economically viable for smaller livestock operations.

Soil P Budgets In simple terms, a soil P budget includes all of the soil P inputs minus all of the soil P removals. It can be calculated by field, farm or region. Soil P budget = Soil P inputs – Soil P removals

Soil P inputs include synthetic fertilizer, livestock manure, wastewater biosolids, other organic amendments, seed and atmospheric deposition. Soil P removals include all of the P that is removed from the field or region in the harvested portion of the crop such as grain, oilseed, hay or meat and bone (in the case of pasture). Phosphorus can also be removed from the soil by runoff, erosion and leaching.

Phosphorus balance indicates that P is being supplied at the same rate as it is being removed. Provided soils have sufficient P fertility, fields, farms and regions in P balance can be managed sustainably over the long-term.

A P deficit indicates more P is being removed from the field, farm or region than is being supplied, primarily by synthetic fertilizer or manure. At the field level, P deficits are unsustainable over the long-term as soils will be “mined” of P. Eventually, a lack of soil P will limit plant growth and yields will suffer.

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A P surplus indicates more P is being supplied than is being removed from the field or region. At the field level, P surpluses will result in a build-up of soil test P. Over the short-term this build-up will improve soil fertility and crop productivity, but, over the long-term increasing soil test P will increase the risk of P loss to surface and groundwater.

On-farm P budgets provide valuable information on the sustainability of P use on the farm over the long-term. They can be used to make on-farm management decisions to optimize P management. Regional P budgets, on the other hand, provide only preliminary insight into the magnitude of any P imbalances in a given region. They may be used for broad planning purposes but are not appropriate for on-farm decision-making. This is due to the loss of detail with aggregation of the data.

Aggregating data to calculate P balances at the regional scale occurs when inputs and removals are collected or grouped by region. Although a region may appear to be in P balance, it is highly unlikely that the entire area is uniform, particularly if the region is very large. More likely, some operations within the region will be in balance while others may have a P deficit or surplus. This is because P inputs and removals are not equally distributed throughout a region. The larger the area over which the P budget is calculated; the less meaningful are the results at the local level. Therefore, significant aggregation, up to a provincial or large watershed level, greatly diminishes the value of the P budget results.

Management Options to Improve P Balance Feed Management to Reduce Manure P Maguire et al. (2005) reported that dietary manipulation strategies may offer the most effective and economically viable means of improving the N:P ratio of manure. These scientists further reported that a combination rather than 4

individual strategies were needed. Various dietary manipulations have been suggested and employed to reduce P in manure in order to reduce soil P loading.

The majority of P (>65%) in grains is phytate-bound and unavailable to monogastric animals (pigs and poultry) that produce little or no enzyme required for the dephosphorylation of phytate P (Selle and Ravindran 2007; Kiarie and Nyachoti 2010). Consequently, available P is provided in the diet through inclusion of supplemental, inorganic P.

Phytate-bound P can be made available through the inclusion of exogenous phytase in the diet (Jongbloed and Lenis, 1997; Nyachoti et al. 2006; Yáñez et al. 2010). Most pig and poultry farmers now include exogenous phytase enzyme in their ration. The use of phytase in the diet decreases the need for supplemental, inorganic P in the diet. A reduction in the supplemental, inorganic P in the diet, in turn, reduces the amount of P that is excreted in the manure.

The inclusion of phytase without reduction in supplemental, inorganic P in the diet can increase P excretion in manure (Vadas et al. 2004; Angel et al. 2005). A recent study in Manitoba suggested that supplemental P addition based on NRC (1998) requirements is too generous and that there is room for further reductions in P without negatively impacting animal performance (Nyachoti et al. 2011). In 2012, the 11th edition of the NRC report – Nutrient Requirements of Swine – was released. While this edition builds on the work in previous editions, it has been significantly updated to reflect rapidly emerging diet modifications.

The use of low phytate grains in the diet (Thacker et al., 2003; Leytem et al., 2004) and feed ingredient processing (Zhang et al., 2003; Nyachoti et al., 2006) can also result in a reduction in the total P excreted in the manure (Yi and Kornegay, 1996; Jongbloed and Lenis, 1997, Ige et al., 2006, Ige et al., 2010).

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Low phytate P grains are genetically modified feedstuff that contains smaller amount of phytate-bound P and greater amount of the readily available P. A recent study conducted in Manitoba showed that feeding low phytate barley grain feeds to finishing pigs significantly increased P digestibility and decreased P excretion in pigs (Ige et al., 2010). The use of highly available P feed ingredients will also reduce the need for supplemental P addition in feed and may offer some economic benefit by reducing the cost of the ration. The use of low phytate P grains is currently not being practiced in Manitoba, likely because low phytate grains are not readily available on the market. The low phytate barley breed produced at the CDC in Saskatoon was just released to the public for breeding in 2009.

Crop Management to Maximize P Removal Crops vary considerably in their removal rates of P. Crop P removal is a function of the quantity of P contained in the harvest portion of the crop and crop yield. Table 1 demonstrates the very significant impact that crop yield can have on the amount of P (expressed as the fertilizer equivalent, P2O5) removed per acre. Good management practices – including soil management, pest control etc. – that maximize yield potentials are essential. High P removal crops, such as high yielding corn and alfalfa, can also be included in the rotation where appropriate to maximize crop P removal. Welsh et al. (2006) reported that a forage-based rotation (wheat – alfalfa – alfalfa – flax) significantly reduced soil test P compared to an annual grain rotation (wheat – pea – wheat – flax). Thus, crop rotation could be a useful management system for regulating soil P build up and, consequently, P loss through run-off. Brown et al. (2006) suggested that intensive cropping system which maximizes P removal from soil can be beneficial for manure nutrient management. He reported that double-cropping with winter forages and silage corn increased total forage production, increased P removal, and reduced soil P concentrations more

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than with corn alone. Ultimately, however, crop choices will depend on the production system and market demand.

Pastures have the lowest P removals because the nutrients removed by the plant are returned to the soil through animal manure during grazing. Maintaining P balance on pastures that are being repeatedly fertilized with pig manure is particularly challenging because P removals are so low.

Table 1. Rates of Phosphorus (as P2O5) removal for various crops 2

Crop

Alfalfa Barley – Grain Canola – Argentine Corn – Grain Corn – Silage Fababeans Flax 3 Grass hay Oats Peas Potatoes – rain fed Potatoes – irrigated Fall Rye Soybeans Sunflowers – not for oil Sunflowers – for oil Wheat – Spring Wheat - Winter

Removal P2O5 per unit of 1 crop 13.8 lb/ton 0.42 lb/bu 1.04 lb/bu 0.44 lb/bu 12.7 lb/ton 1.79 lb/cwt 0.65 lb/bu 10.0 lb/ton 0.26 lb/bu 0.69 lb/bu 0.09 lb/cwt 0.09 lb/cwt 0.45 lb/bu 0.84 lb/bu 1.10 lb/cwt 1.10 lb/cwt 0.59 lb/bu 0.51 lb/bu

Manitoba Yields (per acre) MASC Lowest MASC Top 20% 20% 1.5 ton 20 bu 9 bu 7 bu 1.33 ton 1020 lb 7 bu 0.49 ton 36 bu 9 bu 39 cwt 114 cwt 15 bu 14 bu 310 lb 290 lb 12 bu 19 bu

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4.2 ton 76 bu 38 bu 101 bu 5.78 ton 2550 lb 23 bu 2.66 ton 104 bu 46 bu 270 cwt 272 cwt 65 bu 38 bu 1850 lb 2060 lb 42 bu 72 bu

P2O5 removed per acre (lb/ac) 20.7 – 58.0 8.2 – 31.2 9.4 – 39.5 3.1 – 44.4 16.9 – 73.4 18.3 – 45.6 4.6 – 15.0 4.9 – 26.6 9.4 – 27.0 6.2 – 31.7 3.5 – 24.3 10.3 – 24.5 6.8 – 29.3 11.8 – 31.9 3.4 – 20.4 3.2 – 22.7 7.1 – 24.8 9.7 – 36.7

Removals on a dry matter basis. Adapted from Managing Manure within Tillage Systems and Crop Rotations, Manure Management Facts, MAFRI 2009. 2 Manitoba Agricultural Services Corporation, Static Map Library, Average Yield. 3 Grass hay yields can reach in excess of 4 tons/acre under good soil and fertility conditions.

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Transport of Manure P to a Larger Land Base In November 2013, the new soil test P thresholds under the Livestock Manure and Mortalities Management Regulation (MR 42/98) come into force for all livestock operations in Manitoba. Without improvements in on-farm P balance, the need to haul manure P from areas of high livestock intensity to areas with lower soil test P is inevitable. Transporting liquid manure over long distances is very expensive.

Manure Treatment to Concentrate P Mechanical solid-liquid separation systems are being implemented by some pig farmers in Manitoba located in intensively developed areas. These systems, however, are extremely expensive to purchase, install and operate. Manitoba Agriculture, Food and Rural initiatives is currently offering to pay 75% of a solidliquid separation system up to $500,000 for pig operations to facilitate compliance with the soil test P thresholds.

The adoption of multi-celled manure storage structures, and their management as gravity separation systems that settle out the P-rich solids for transport out of the region, may improve the economics of solid-liquid separation.

OBJECTIVE OF THE REPORT Regional P budgets provide insight into the P status of a region. They provide preliminary information on the sustainability of the fertility practices in a region and they could be incorporated into future policies on livestock development. The objective of this report is to provide P budget estimates for each Rural Municipality in agro-Manitoba. Original P budget estimates were made by Gyles (2009) using 2006 livestock inventory data from Statistics Canada. However, significant changes to the livestock industry, including reductions in cattle and pig populations, have occurred since 2006. 8

Within the last decade, livestock operations have become more intensive. The total number of livestock operations has declined while the number of animal per operation has increased. Between 2001 and 2010, the number of pig farms in Manitoba decreased from 1,668 to about 760, a decrease of more than 50%. Within the same period, the number of pigs per farm increased from 1495 to 3400 (Honey, 2010; Statistic Canada, 2010).

Starting in 1995, pig production in Manitoba witnessed a steady growth until it peaked in 2007. Various market conditions, environmental pressures and the USA’s mandatory Country of Origin Labelling (COOL) legislation have contributed to the gradual reduction in pig production. Annual pig production fell from 9.45 million market hogs in 2007 to about 8.24 million in 2010, a drop of 12.8%.

The number of beef cattle farms in Manitoba has also decreased from 10,755 in 2002 to 8,500 in 2010. Total number of beef cattle increased from 1.39 million in 2002 to a peak value of 1.64 million in 2005 (Statistic Canada, 2006). Starting in 2006 there was a gradual reduction in the number of beef cattle in Manitoba. By January of 2011 the number of cattle in Manitoba had fallen to 1.16 million, a decrease of 29.3% since 2005.

Given the reduction in beef and pig numbers in Manitoba since 2006, revised P budget estimates are warranted and are presented herein.

METHODS In order to create a P budget for a specific municipality it is necessary to determine the P inputs and P removals for that RM. The approach used in the Gyles (2009) model was similar to the approach developed by Nicolas et. al. (2002). The all-encompassing approach used by Nicolas et. al. (2002) is complex and can be simplified to the major components by focusing only on soil 9

inputs and outputs to develop a soil P budget estimate. Soil P budget = Soil P inputs – Soil P removals

Calculation of P Inputs The potential soil P inputs are: 1. Animal manure; 2. Synthetic fertilizer: 3. Seed; 4. Atmospheric deposition; and 5. Municipal waste

1.

Animal Manure

The total manure P inputs for each RM were calculated as follows:

Manure P in RM for each Livestock Category = Number of Animals in RM x Quantity of P Excreted per Animal per Cycle x Number of Cycles Total Manure P inputs for each RM = ∑ Manure P in RM for all Livestock Categories Animal numbers for each RM were obtained from Statistics Canada’s 2006 Census of Agriculture and then adjusted using the January 2011 inventories of cattle and pigs. The quantity of P excreted per animal per cycle and the number of cycles for each livestock type are provided in Table 2. The P excretion estimates (expressed as P2O5) for livestock in Manitoba (Table 2) are average “book” values that were developed by Manitoba Conservation (Trudelle, 2008 adapted from Centre de Référence en Agriculture et Agroalimentaire du Québec, 2003). Actual P excretion depends on farm management and is strongly influenced by feeding practices particularly the total amount of P in the diet.

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Table 2. P2O5 Excretion Estimates for Livestock in Manitoba Animal Type Kg Cycles Dairy calves 14 1 Beef Backgrounder 16.5 1 Feeder cattle 16.5 1 Backgrounder 16.5 1 Cow/calf 27.4 1 Dairy cows 52 1 Dairy Heifers 32 1 Feeder cattle 27.4 1 Rams 6.04 1 Ewes 6.22 1 Lambs 0.74 1 Broilers 0.0402 6.5 Pullets under 19 0.068 2.5 Laying hens 19 weeks and over 0.367 1 Other poultry 0.07 1 Turkey (< 9,9 kg) 0.161 2.8 Boars 16.7 1 Sows and gilts for breeding 16.7 1 Nursing and weaner pigs 0.167 6.4 Grower and finisher pigs 2.05 2.9 Horses and ponies 14 1 Goats 3 1 Wild Boar 16.7 1 Bison 17 1 Llamas and Alpacas 6.22 1 Deer 14 1 Elk 14 1 Source: Adapted from Centre de Référence en Agriculture et Agroalimentaire du Québec, (2003) by Trudelle (2008)

2.

Synthetic Fertilizer

The total synthetic fertilizer P inputs for each RM were calculated as follows:

Total Fertilizer P inputs for each RM = Total P2O5 sold in MB x Proportion $ spent in RM on fertilizer

The amount of P2O5 sold annually for agricultural purposes in Manitoba was obtained from the Canadian Fertilizer Institute (2007).

The proportion of total provincial dollars spent on fertilizer that are spent in each municipality was estimated using Census of Agriculture (2006) values. The total 11

fertilizer P inputs for each RM was then calculated by multiplying the total amount of P2O5 sold in Manitoba by the fraction of provincial fertilizer dollars spent in that municipality.

3.

Seed

The total seed P inputs for each RM were calculated as follows:

Total Seed P inputs for each RM = Total Crop Acres per crop x Seeding Rate x Seed P Concentration

Phosphorus is also added to the soil in the form of seed when a field is seeded. The total amount of seed-P added to soil in a municipality can be estimated by determining crop acres for each crop type using the Census of Agriculture (2006) values and multiplying the crop acres by the seeding rate and the amount of P in the seed. Concentrations of P in seed were adapted from the Canadian Fertilizer Institute (2001) values for P removal in crops. When these data were presented as a range of values the midpoint value was used. Seeding rates and CFI removal rates for P are shown in Table 3.

4.

Atmospheric Deposition

Phosphorus that is added to soil from dust that settles out of the atmosphere or is washed out of the atmosphere in precipitation is called atmospheric deposition. Nicolas et. al. (2002) used a value of 0.1 kg P/ha/year. However, the quantity of P that ends up on agricultural land as a result of atmospheric deposition is assumed to be insignificant and as such was not included in the P budget calculations.

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Table 3. CFI Crop P2O5 Removal Rates and Seeding Rates Crop

P2O5 removal lbs/unit low

alfalfa and mix barley canola corn for silage flax forage seed grain corn mixed grains oats other hay and fodder rye soybeans spring wheat sunflower winter wheat durum dry white beans other dry beans canary seed Field peas potatoes mustard buckwheat triticale

high 12 0.375 0.94 11.4 0.583 0.005 0.39 0.43 0.23 9 0.45 0.8 0.525 0.007 0.46 0.525 0.0138 0.0138 0.004 0.62 0.0825 0.94 0.009 0.525

units 14.7 ton 0.463 bu 1.14 bu 14 ton 0.7083 bu 0.005 lb 0.48 bu 0.43 bu 0.28 bu 11 ton 0.45 bu 0.857 bu 0.65 bu 0.009 lb 0.56 bu 0.65 bu 0.0138 lb 0.0138 lb 0.005 lb 0.76 bu 0.1 cwt 1.14 bu 0.0095 lb 0.65 bu

Seeding Rate units/ac

units 2.5 lb 2 bu 0.120 bu 0.214 bu 0.589 bu 5 lb 0.214 bu 1.8 bu 2.3 bu 2 bu 1.2 bu 1.667 bu 2 bu 4 lb 2 bu 2 bu 60 lb 60 lb 40 lb 2 bu 23 cwt 0.120 bu 42 bu 2 lb

Source: Gyles (2009) and Canadian Fertilizer Institute (2001)

5.

Municipal Wastewater and Biosolids

Some municipalities may have a measureable amount of P added to agricultural land in the form of municipal biosolids or irrigation of municipal waste-water. Whether values for the amount of land-applied biosolids can be acquired is not certain. The amount of P added to agricultural soils in the form of municipal wastes was not included in the calculation of the P budgets.

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Calculation of P Removals The potential soil P removals are: A. Harvested plant material; B. Cattle grazing on pasture; C. Residue removal or burning; D. Runoff; and E. Soil erosion (wind and water)

A.

Harvested Plant Material

Phosphorus is removed from the soil in the form of plants and plant products such as grain and forage or meat in the case of grazing cattle on pasture. The total P removed in each RM in the harvested portion of the plant can be calculated as follows:

Crop P removal by crop type = Acres planted by crop x Long-term yield average for each crop type x Crop P2O5 removal rate per unit of crop Total Crop P Removal for the RM = ∑Crop P removals for all crops grown

Acres planted to each crop were obtained from 2006 Census of Agriculture data. Long-term average yields (2001-2007) for each crop were calculated for each municipality using Manitoba Agricultural Services Corporation (MASC) data. If a specific yield was not available the average from a nearby municipality with sufficient data was used. Crop P removal rates per unit of crop (Table 3, expressed as P2O5) were adapted from the Canadian Fertilizer Institute (2007). When data were presented as a range of values the midpoint value was used.

B.

Cattle Grazing on Pasture

The total P removed in each RM in by cattle grazing on pasture can be calculated as follows:

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P removal by cattle grazing on pasture = Acres in pasture x 10 kg P2O5 per acre

The P removal rate by cattle grazing on pasture was estimated at 10 kg P2O5 per acre (Entz, 2008 pers. comm.). This rate is also consistent with Wilson et. al (2010).

C.

Residue Removal or Burning

An unknown amount of P could also be removed in the form of removed or burned cereal and flax straw; however, the amount that is not eventually returned to the land is assumed to be very small for most municipalities in Manitoba. As such, P removal from cereal and flax straw removal or burning was not included in the P budget calculation.

D.

Runoff

The value used by Nicolas et. al. (2002) for the amount of soil P lost in run-off was 0.3 kg P/ha/yr from perennial crops and 0.5 P/kg/ha/yr from annually cropped land. This value was determined to be insignificant and as a result was not included in the P budget calculation. Organic matter that is removed from the soil during run-off will also remove P from the soil system. Nicolas et. al. (2002) used 0.3 P/kg/ha/yr and 0.5 P/kg/ha/yr as the amount of actual P from organic matter removed from perennial and annual crop land, respectively. This value was also determined to be insignificant and as a result was not included in the calculation.

E.

Wind Erosion

Nicolas et al. (2002) found no literature values for the amount of P lost from soil in the form of dust. This value was also determined to be insignificant and as a result was not included in the calculation.

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RESULTS The original P soil budgets calculated by Gyles (2009) using 2006 animal inventories are shown in Table 4. Negative values indicate a P deficit while positive values indicate a P surplus.

Table 4. Phosphorus Surplus or Deficit by RM Using 2006 Animal Inventories

RM

Phosphorus Surplus or Deficit (kg P205/ha)

Albert Alexander Argyle Armstrong Arthur Bifrost Brenda Brokenhead Cameron Cartier Coldwell Daly De Salaberry Dufferin Edward Elton Eriksdale

-0.91 -4.25 -2.63 -13.66 -6.63 -4.36 -2.98 -0.48 -3.16 10.82 -13.48 -0.64 3.46 4.61 -7.93 0.66 -11.16

Fisher Franklin Gimli

-6.87 -3.14 -3.73

Phosphorus Surplus or Deficit (kg P205/ha)

RM Pipestone Portage la Prairie Reynolds Rhineland Ritchot Riverside Roblin Rockwood Roland Rosser Sifton Siglunes South Cypress South Norfolk Springfield St. Andrews St. Clements St. Francois Xavier St. Laurent Stanley

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-1.73 -0.78 -0.79 4.18 2.49 1.93 -0.12 -3.12 4.23 -3.52 -6.99 -9.64 0.51 8.37 0.34 -4.04 -0.52 1.53 -11.38 -0.75

Table 4 Cont’d______________________________________________ Glenella Glenwood Grahamdale Grey Hanover Headingley La Broquerie Lac du Bonnet Lakeview Lansdowne Lorne Louise

-2.90 -0.93 -8.68 3.85 35.63 4.82 101.01 -7.69 -9.89 -2.05 4.83 -2.44

Ste. Anne Strathcona Stuartburn Tache Thompson Turtle Mountain Victoria Wallace West St. Paul Westbourne Whitehead Whitemouth

18.71 1.67 -11.09 11.12 2.01 1.00 -4.17 -2.46 0.24 1.71 -3.95 11.21

Macdonald

4.85

Whitewater

0.02

Montcalm

3.26

Winchester

-1.65

Morris

6.34

Winnipeg

11.98

Morton

-7.32

Woodlands

-6.50

North Cypress

3.73

Woodworth

-7.38

North Norfolk

4.23

CAR 3*

-9.27

Oakland

-2.58

CAR 4*

-11.51

Pembina

0.51

CAR 5*

-8.10

Piney

2.04

CAR 6*

-11.88

*In some areas RM level census levels violated privacy rules. For Census Agricultural Regions (CAR) 3 to 6 all RMs were aggregated.

Revised P budgets for each RM using 2011 inventories for cattle and pigs are shown in Table 5. The reduction in pig and cattle numbers between 2006 and 2001 resulted in greater deficits and smaller surpluses across Manitoba. A complete P budget for the RM of Arthur is provided in the Appendix (Tables A.1 to A.3).

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Table 5: P Inputs, Removals and Budgets by RM using 2011 Pig and Cattle Inventories

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Table 5: P Inputs, Removals and Budgets by RM using 2011 Pig and Cattle Inventories (cont’d)

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Phosphorus budgets between -5 to +5 kg P2O5/ha were considered to be in balance whereas P budgets less than -5 kg P2O5/ha were considered to be in deficit and more than 5 kg P2O5/ha was considered to be in surplus. Of the 78 RMs assessed, 51 were in or approaching P balance (Map 1). Fifteen of the RMs and each of the remote Canadian Agricultural Regions (CARs 3 to 6) showed a P deficit of greater than 5 kg P2O5/ha. Most of these RMs are located in the northern half of agro-Manitoba (Map 1).

Nine RMs showed a P surplus due to a combination of synthetic P2O5 fertilizer and manure inputs exceeding crop P2O5 removals by more than 5 kg P2O5/ha (Map 1).

Excluding synthetic fertilizer from the calculation, although impractical, gives an indication of the P budgets as a result of livestock alone. When synthetic fertilizer is excluded, only Hanover and La Broquerie showed a P surplus due to their livestock inventories (Map 2). As well, Ste. Anne appears to be approaching P balance based on its livestock inventory (Map 2).

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Map 1. Soil P budget estimates by RM for agro-Manitoba.

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Map 2. Soil P budgets (excluding synthetic fertilizer)by RM for agro-Manitoba.

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CONCLUSIONS Significant reductions in cattle and pig populations in Manitoba since 2006 warranted a recalculation of soil P budgets by RM.

The revised budgets demonstrated that most municipalities in southern agroManitoba are in P balance. This indicates that these RMs are replacing the P that is removed in the harvested portion of the crop with synthetic fertilizer and manure. Soil fertility in these RMs should be sustainable over the long-term if beneficial management practices are employed.

In 15 RMs, mostly in the northern half of agro-Manitoba, more P is being removed from the soil than is being replaced with synthetic fertilizer and manure. A P deficit indicates that these RMs are “mining” the soil of P. This practice results in decreased yields and is not sustainable over the long-term.

There are only 9 municipalities that have a surplus of P. Seven of these could achieve P balance by replacing synthetic fertilizer inputs with manure. Two municipalities in Manitoba, specifically Hanover and La Broquerie, have a significant P surplus due to livestock alone.

Management of P surpluses at the farm level requires more detailed on-farm P budgets to determine which operations have the surplus and the magnitude of the problem. Phosphorus surpluses at the farm level result in over-application of manure P to land, build-up of soil test P and will make compliance with the soil test P thresholds challenging. These operations should explore all opportunities to minimize feed P and synthetic P fertilizer inputs to reduce their P surpluses. Where P balance cannot be achieved, more intensive P management strategies – including export of manure P with or without treatment or a reduction in animal numbers – will be required to bring these operations into P balance.

23

Acknowledgments Funding was provided by the Agri-Food Research and Development Initiative (ARDI) under the Canada-Manitoba Growing Forward Initiative, and by the Manitoba Livestock Manure Management Initiative.

The authors would like to acknowledge the contributions of Ron Tone and Joel Tone of Tone Ag Consulting Ltd. who supplied information regarding manure production per animal species.

The authors would also like to acknowledge Ian Kirby of MAFRI for preparing the Soil Phosphorus Budget maps.

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APPENDIX Table A.1. Phosphorus Contributions from Livestock in the RM of Arthur 1.0 ADDITIONS 1.1 Manure

/year

Dairy calves Beef Backgrounder Feeder cattle Backgrounder Cow/calf Dairy cows Dairy Heifers Feeder cattle

P205/head 1 14 1 16.5 1 16.5 1 16.5 1 27.4 1 52 1 32 1 27.4

Total Cattle P205 (Kg) 2011 Inventories

/year 1 1 1

P205/head 6.04 6.22 0.74

Broilers, roasters and Cornish hens Pullets under 19 weeks intended for laying Laying hens 19 weeks and over Other poultry Turkey (< 9,9 kg) Total Poultry P205 (Kg)

6.5 2.5 1 1 2.8

0.0402 0.068 0.367 0.07 0.161

Boars Sows and gilts for breeding Nursing and weaner pigs Grower and finisher pigs Total Hog P205 (Kg) 2011 Inventories

1 1 6.4 2.9

16.7 16.7 0.167 2.05

1 1 1 1 1 1 1

14 3 16.7 17 6.22 14 14

Rams Ewes Lambs Total Sheep P205 (Kg)

Horses and ponies Goats Wild Boar Bison Llamas and Alpacas Deer Elk

TOTAL Manure P2O5 ADDITIONS (KG)

RM of Arthur Animals P205 (Kg) 3244.01 45416.13 467.1 7707.15 302.058 4983.957 400.9275 6615.304 4039.637 110686 0 0 0 0 202.41 5546.034 180954.6179 Animals P205 (Kg) 9 54.36 310 1928.2 383 283.42 2265.98 Animals P205 (Kg) 426 111.3138 134 22.78 94 34.498 15 1.05 50 22.54 192.1818 Animals P205 (Kg) 3.5648 59.53216 20.4976 342.3099 20.4976 21.90783 20.4976 121.8582 545.61 8.38654 Animals P205 (Kg) 201 2814 59 177 0 0 0 0 3 18.66 0 0 0 0 3009.66 186968.0478

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Table A.2. Phosphorus Contributions from Seed for RM of Arthur 1.2 Fertilizer Total Manitoba Fertilizer Expenditure $351,136,399 CFI P205 Sold in MB (Kg) 106,600,000 $ P205 (Kg) Fertilizer and Lime Expenidure / R.M. 2886406 876,271.67 Total Fertilizer P205 (Kg) 876271.6724 1.3 Seed 2006 CROPS (acres) P2O5 additions lbs/unit units/ac low high Seeding Rate Units Acres P205 (lbs) alfalfa and mix 0.0050 0.0050 2.5 lb 12991 162.3875 barley 0.38 0.46 2 bu 4990 4181.62 canola 0.94 1.14 0.120 bu 23222 2898.1056 corn for silage 0.39 0.48 0.214 bu 1205 112.323214 flax 0.58 0.71 0.589 bu 6258 2380.99579 forage seed 0.0050 0.0050 5 lb 213 5.325 grain corn 0.39 0.48 0.214 bu 778 72.5207143 mixed grains 0.43 0.43 1.8 bu 123 95.202 oats 0.23 0.28 2.3 bu 15068 8645.265 other hay and fodder 0.38 0.46 2 bu 3113 2608.694 rye 0.45 0.45 1.2 bu 6591 3559.14 soybeans 0.80 0.86 1.667 bu 0 0 spring wheat 0.53 0.65 2 bu 48721 57247.175 sunflower 0.0070 0.0090 4 lb 11429 365.728 winter wheat 0.46 0.56 2 bu 1983 2022.66 Durum 0.53 0.65 2 bu 857 1006.975 dry white beans 0.0138 0.0138 60 lb 0 0 other dry beans 0.0138 0.0138 60 lb 439 363.492 canary seed 0.0040 0.0050 40 lb 120 21.6 Field peas 0.62 0.76 2 bu 1610 2221.8 potatoes 0.0825 0.10 23 cwt 148 310.615 mustard 0.94 1.14 0.120 bu 239 29.8272 buckwheat 0.0090 0.0095 42 bu 118 45.843 triticale 0.53 0.65 2 lb 0 0 Sum 88357.294 TOTAL SEED P2O5 ADDITIONS (KG) 40,078.87

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Table A.3 Phosphorus Removals and P Budget for RM of Arthur 2.0 REMOVALS 2.1 Crops Crop alfalfa and mix barley canola corn for silage flax forage seed grain corn mixed grains oats other hay and fodder rye soybeans spring wheat sunflower winter wheat Durum dry white beans other dry beans canary seed Field peas potatoes mustard buckwheat triticale

P2O5 removal lbs/unit (except straw) low high Units 12 14.7 Tons 0.375 0.463 bu 0.94 1.14 bu 11.4 14 Tons 0.583 0.7083 bu 0.005 0.005 Lbs 0.39 0.48 bu 0.43 0.43 bu 0.23 0.28 bu 9 11 Tons 0.45 0.45 bu 0.8 0.857 bu 0.525 0.65 bu 0.007 0.009 lbs 0.46 0.56 bu 0.525 0.65 Bu 0.0138 0.0138 Lbs 0.0138 0.0138 Lbs 0.004 0.005 Lbs 0.62 0.76 Bu 0.0825 0.1 cwt 0.94 1.14 bu 0.009 0.0095 lbs 0.525 0.65 bu

TOTAL CROP P2O5 REMOVALS (KG) 2.2 Pasture Acres tons/ acre P2O5 removal kgs/unit Pasture Removal Rate 1 9 TOTAL PASTURE P2O5 REMOVALS (KG) TOTAL P2O5 REMOVALS (KG) 3.0 ADDITIONS - REMOVALS Net Total (Kg) Land (ha) Surplus (kg/ha) Surplus (lbs/acre)

27

Avg Yield (tonne/acre) P205 (lb) 1.487 257890.187 50.305 105178.197 24.735 597372.017 7.22 110491.27 16.711 67520.4228 546.74 582.2781 38.173 12918.8884 43.926 2323.24614 68.461 263050.439 1.22 37978.6 41.567 123285.644 0 0 31.783 909743.482 1177.2 107633.75 46.063 46584.8938 22.893 11526.3393 0 0 1406.5 8520.8583 595.7 321.678 38.17 42403.053 233.488 3153.25544 706.8 175682.208 564.37 616.009855 0 0 Sum lbs 2884777 1,308,535 31527.489 11 315274.89 1623809.609 -520,491 70737 -7.36 -6.56

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