dates from fire scars or age class data on the monument map. ...... sword fern bracken fern ... from similar camera points (Figures 2, 3, and 4). In 1916, there was ...
ULoQ.mtNI I 29.2: OR 3/3x
OREGON CAVES FOREST AND FIRE HISTORY
James K. Agee Laura Potash Michael Gracz College of Forest Resources University of Washington Seattle, Washington
National Park Service Cooperative Park Studies Unit Report CPSU/UW 90-1
Winter 3990
TABLE OF CONTENTS
Executive Summary
.
.
.
.
.
.
.
.
i
Introduction
.
.
.
.
.
.
.
.
.
.
1
Methods
.
.
.
.
.
.
.
.
.
.
3
.
4
.
Forest Classification
.
.
.
.
.
Fire History
.
.
.
.
.
.
.
.
.
8
Fire Behavior
.
.
.
.
.
.
.
.
.
11
.
.
.
.
.
.
.
.
.
14
.
14
Results
.
.
Community Classification
.
.
.
. .
.
.
.
.
.
20
.
.
.
.
.
.
33
Fire Behavior in the Developed Area.
.
.
.
51
.
.
.
.
64
Community Descriptions Fire History
.
Literature Cited .
.
.
.
.
.
.
Appendix A: List of Plants Appendix B: Vegetation history of Kinney Creek
SOUThERN 0"E,3EON UNIVERSHY Lisipl ASHLAND, OREGON 97520
SOUTHERN OREGON UNIVERSITYLIBRARY
3 5138 00643656 9
EXECUTIVE SUMMARY
This study was designed to classify the forests of Oregon Caves National Monument, to define the fire history of the monument, and to analyze fuel conditions around the developed area.
Four were
Seven plant community types were identified.
widespread at Oregon Caves: the Douglas-fir/oak type, the Dry white fir/Douglas-fir type, the Mesic white fir/Douglasfir type, and the White fir/herb type.
The other three
communities were of limited extent: a Meadow type, an Oak woodland type, and an Alder type.
The Douglas-fir/oak type
represents the upper bounds of the Mixed Evergreen Zone in southwest Oregon, and is found around the developed area of Oregon Caves.
The other widespread types represent variants
within the White Fir Zone of southwest Oregon.
The White
fir/herb type is the highest elevation community type at Oregon Caves and is transitional to the Red Fir Zone of southwest Oregon.
It contains the oldest trees at the
monument.
Fire history was determined by an area frequency method called natural fire rotation (NFR).
The average NFR over
the last 500 years has been about 76 years.
The 19th
century had the most fires, with an average NFR of 34 years. The Douglas-fir/oak type had the most frequent fire of the i 't I . ,&
community types, averaging 60 years.
During this time, some
areas may have burned twice and others not at all.
Multi-
aged stands are common, and are the result of relatively frequent underburning.
Even the "old-growth" stands at
Oregon Caves have underburned several times.
The 1982 fuel reduction project significantly reduced surface fire potential in the treated area.
However, the
presence of many snags, which were not included in the 1982 treatment, and regrowth of brush since the treatment, will require repeated fuel manipulation if reduced fire hazards are to be maintained.
ii
INTRODUCTION
Oregon Caves National Monument was established to preserve a cave system dubbed "The Marble Halls of Oregon" by Joaquin Miller.
First located by settlers in 1874, the cave and 480
acres of surrounding land was declared a national monument in 1909 and was managed by the Forest Service until 1933, when its management was transferred to the National Park Service.
National monuments are intended to preserve "at
least one nationally significant resource", and are "usually smaller than a national park and lack its diversity of attractions".
The cave feature is the primary resource of
the monument, but the biotic resources are also significant.
Nestled within the Siskiyou Mountains, Oregon Caves National Monument (Figure 1) lies within a forest region more diverse and complex than any other in the West (Whittaker 1960).
A
combination of geological scale vegetation history, climatic-topographic-edaphic diversity, and the transitional location of these mountains between floras of diverse climatic relations make the Klamath Region the most central of the forest floras and forest vegetation of the West (Whittaker 1960).
Another aspect of the Siskiyou Mountains
that add to forest diversity and pattern is disturbance history. Fire appears to be the dominant disturbance process in the forests of the Siskiyou Mountains.
__Si:- ........................a'1 d
Other disturbances, such
Figure 1. Location of Oregon Caves National Monument in southern Oregon. The monument is surrounded by the Siskiyou National Forest.
as floods, mass movement,
ice storms, wind,
and insect or
disease epidemics have also played important but more local or infrequent roles in the past (Atzet and Wheeler 1982). In addition to the various physical and biological effects that fire creates, there are important cultural implications of fire in the Siskiyous. sources,
People are major ignition
and have been so for centuries.
developments are often intermingled, urban-forest interface.
Forests and
a situation called the
This commingling is true throughout
the valleys of the region, and the prime local example is the developed area of Oregon Caves National Monument.
Two large management projects related to forest fire hazards have occurred in the developed area of the monument in the last twenty-five years.
In 1962,
a small clearcut operation
removed a number of "hazard trees" in the area above the
2
chalet-chateau complex.
In 1982, a fuel hazard reduction
project was completed below the chateau over about 30 acres; understory trees and brush, as well as small dead fuels, were manually removed or pile burned and residual trees were thinned.
Most snags and downed logs were left.
Continued
forest management will be needed to minimize conflicts between the forest values and those of the developed area. This study of the forest and fire history of Oregon Caves National Monument was generated as part of a larger study of fire ecology in the national parks of the Pacific Northwest. Although a small part of the total study, this report is clearly important in the management of the monument's forest resources for the benefit of society.
The results of this
study can be used in better understanding the forests of the monument and the region, and the history and current management of fire at Oregon Caves.
The study was designed in three parts: the forest types of the monument;
(1) classification of
(2) defining the fire
history of the monument; and (3) analyzing the effectiveness of the 1982 fuel manipulation on current and future fire behavior in the vicinity of the chateau.
METHODS Field work on this project occurred during 1988 and 1989. The forest ecology and classification work was completed 3
during 1988,
while the fire history and fire behavior work
began in 1988 and was completed in 1989.
Forest Classification Field Work.
The objective of sampling for forest
classification was to determine major forest types, structure, and composition at Oregon Caves, to determine vegetation history, monument.
and to add to the species list for the
Sampling intensity was roughly 1 plot per ten
acres, or 50 plots for the 488 acres of the monument.
Plots
were subjectively chosen, given the constraints on spacing implied by the 1 per 10 acre constraint.
Additional data on
disturbance history were collected in addition to the classification data. observations recorded,
Plots were normally 10 X 10 m for most although a few plots in widely spaced
stands were as large as 20 X 20 m.
The plot was located in
a homogeneous portion of the stand (if the stand was clearly two-aged or -sized, the plot encompassed that variation;
if
it was a mix of single and two-aged stands over a large area,
one plot was placed in each).
On each plot, a number was assigned (OC-1 to OC-50) located on the monument map.
Elevation, aspect,
and slope
compass, and clinometer.
were recorded by altimeter,
and
For
trees, all the species present were tallied in one of three height classes: tall.
0-3 meter tall, 3-10 meter tall,
>10 meter
Basal area was recorded by the prism method from the 4
center of the plot (which may include trees off the fixed plot and exclude trees on the plot).
The height of the
tallest tree of each species was recorded to the nearest m by clinometer.
Percent cover of each tree species was (1 = 1-5 percent,
recorded by cover class
2 = 6-25 percent;
3 = 26-50 percent; 4 = 51-75 percent; 5 = 76-95 percent; and 6 = 96-100 percent). The 3-5 most common shrubs found in the vicinity of the plot (i.e.,
perhaps 50 X 50 m area)
were
listed to obtain a representative sample of shrubs present, and the cover class (1-6)
for each species was recorded.
The same technique was used for herbaceous vegetation.
A
species list was built as part of the sampling.
Community Classification and Gradient Analysis.
A major
objective of the project was to define the major forest communities of the monument and relate these communities to the major environmental gradients affecting their distribution.
A Two Way Indicator Species Analysis
(TWINSPAN) was used to delineate major plant communities objectively. Hill
TWINSPAN is a FORTRAN program developed by
(1979) which uses an eigen-analysis to dichotomously
divide groups
(plots), based on the presence and abundances
of similar and/or dissimilar attributes
(species).
The
program also divides attributes dichotomously based on presence and abundance in groups, hence the 'Two Way Analysis'.
5
In the analysis presented here all default options were used except that rare species were downweighted in importance to simplify the descriptions.
If a species was present in the
lowest cover category it was given half the weight of the species present in other cover categories when the TWINSPAN program drew lines between dissimilar groups.
Detrended Correspondence Analysis (DECORANA) was used to plot species and plots in two dimensional space.
This space
was then visually and statistically analyzed to identify possible environmental gradients within which the plant communities are found at the monument.
DECORANA is an
ordination technique which artificially removes an 'arch effect' in ordination space which can occur when using other ordination techniques, confusing interpretation of environmental relationships among plots and/or species.
The
effect results from a correlation of axis 1 scores with axis 2 scores.
Multiple regression and multiple discriminant analysis were used to define possible relationships of TWINSPAN/DECORANA delineated communities with measured environmental variables.
The regression technique was used in examining
relationships between respective variables and DECORANA axis scores. of slope,
In addition to the measured environmental variables aspect and elevation,
6
two 'new' variables were
---
created to accurately reflect moisture gradients possibly associated with aspect. and Stage (1976),
Following Agee and Kertis
(1987)
cosine aspect and sine aspect were used
along with slope to develop a regression equation which might help explain environmental causes of plant community distribution.
The independent variables were the
environmental measures and the dependent variables were raw axis 1 and 2 scores from DECORANA.
Discriminant analysis was used to explore which environmental variables may have been important in explaining TWINSPAN divisions.
Discriminant analysis also
examines how well that classification holds when environmental variables are used to explain the divisions which are based on plant occurrence and cover.
Discriminant
groups were enumerated based on TWINSPAN divisions.
The
plots from the Dry and Mesic White Fir/Douglas-fir communities were combined to produce a clearer analysis. Slope,
cosine aspect, and elevation produced the best Box's
M test for unequal covariance matrices and were used as the discriminating variables.
After the plots sampled were analyzed using the multivariate techniques mentioned above, the resulting community data were summarized.
Means of densities by species and height
class, basal area by species, height of tallest tree by species, and percent cover by species were calculated for
7
N
trees within a given community type.
Constancy (relative
frequency of a species by plot within community expressed as a percent) and mean percent cover were computed for herbs and shrubs. Fire History Another important element of this project was to obtain disturbance information about each site, either through coring trees for ages or scars or sampling fire wedges.
An
attempt to minimize taking wedge or stem cross-sections was made, using increment core techniques to sample scars whenever possible.
In no cases were such potential wedge
samples located within sight from a road or trail. On each plot, several trees in each size class were aged, averaging about 10 trees per plot.
Samples were cored to
the center of the tree and as low to the ground as possible. For each tree sampled (scar sample, tree cored for pith, clipped tree) a plot number, tree number, species code, diameter at breast and core height, bark thickness, and tree height were recorded.
Scars were sampled using the
increment core technique of Barrett and Arno (1988) whenever possible rather than wedge sampling.
Most of the
destructive sampling was done on stumps in surrounding Forest Service clearcuts or areas near the boundary of the monument, with prior permission from the Forest Service for all sampling.
Samples were returned to the laboratory and
8
sanded.
Ages of core or wedge samples were dated using a
dissecting microscope.
Dates from tree ages and fire scars were located on topographic maps of the monument and surrounding lands. Fire events, defined either as single fires or a series of closely spaced fires, were reconstructed in priority order using (a) fire scars from wedge samples,
(b) cores
specifically extracted to date a fire scar,
(c) cores
exhibiting aberrant ring patterns, generally associated with dates determined from (a) or (b), and (d) age class data, particularly where severe fires had removed previous evidence.
Only early seral species (such as Douglas-fir in
white fir series plant communities) were used as evidence of disturbance when age class data were used to estimate a date of disturbance.
Most of the scar dates were from increment core samples, or stumps adjacent to the monument.
Because stump counts were
made in the field, crossdating was not possible and fire events were usually defined on the basis of closely-spaced scars together with age-class data from the plots. Precision is estimated to be plus or minus: 10 years for samples before 1700, 5 years for samples between 1700-1800, and 2 years or less for samples after 1800.
9
Fire events were constructed by first placing significant dates from fire scars or age class data on the monument map. To be considered a fire event, one of the following conditions had to occur: two scars of the same time period, 1 scar plus establishment of early seral trees, or consistent age classes of later seral species (such as white fir) at higher elevation.
Single scars were common but were
deemed localized events and were not considered in the analysis.
Where closely-spaced dates occurred, circles of
250 m radius were drawn around the locations containing each date (Figure 2).
The extent of the fire was reconstructed
by joining the circles, except that circles were not
1875-76
.0Tree/Scar date
Figure 2. Historic fire extent was reconstructed by locating fire scars or contemporary early seral trees that germinated and drawing 250 n circles around each one. The boundary of the fire was then drawn around those circles.
10
connected if the space between them was larger than a circle diameter, except when the space was more than 2/3 encircled already.
The boundary of the fire was then adjusted
slightly to account for topographic influences on fire behavior: for example, ridgelines were often followed even if the circles slightly overlapped the ridge.
Each fire
event was separately mapped.
Fire return intervals were calculated using the natural fire rotation (NFR)
method (Heinselman 1973).
A selected time
interval divided by the proportion of the study area burned within that time interval yields the NFR.
Generally, the
NFR method produces conservative estimates of fire frequency, because of the need to reconstruct past fire events.
NFR's were calculated by century and by forest
community type by segregating burned area either by time or by area of present-day community type burned by each fire event.
Fire Behavior
The fire behavior portion of the study was designed to evaluate the effectiveness of the 1982 fuel reduction Potential fire hazard and
project below the chateau.
buildup over time was evaluated to help design periodic maintenance treatments.
11
Shrub Reg~rowth.
Shrub
-regrowth and cover were measured on
three transects.- acr-oss= Cave Creek be lowth 3).
AveracG cov11er a-nd averagen heigVh, wA,-r,-
each transect fo
growth bet-vw~en
(Arbutus menziesiil)
(Figure
calculated along
eao~n of the miajor shnru,-b species
For Paci~fic madrona densiflorus),
chateau
tanoak
-in 1988.
(Lithocarpus
and canyon 'Live oak (Quercus chrysolepis), L9S2-CE, was
to show how each
species has recovered since the fuel manipulation.
These
data were also used in fire behavior predictions for the areas below the chateau.
Late season fuel moisture samples
were collected for each of these specles as an additional input to the fire behavior prediction process.
Snags and Downed Logs.
All snags greater than 5 m tall1-
within the fuel manipulated area
(Figure 3) were mapped.
Height, species, diameter, and decay class were measured.
Snags were segregated
into
five geogqraphical zones related
to di-stance from t-he chateau: Zone 21, 0-50 mn; Zone 2, 50-100 m;
Zone 3. 100-150 m.;
Zone 4, 150-200 r;
and Zone 5, >200 m.
Snag mass was calculated -fromt dimtrand height measurements uas ng the Intenaina (Avery and Burkhna---
1983
a-,i
cg rule for taper
::djusa--ed -fo-r decay class using
density estoimat-es from,.gee and Huff(18) were measured along three trnet intersect method
(Brown 1974).
Downed logs
Figure 2) by the line
Log mass was calculated by
transect, US 4jng densi',ty est~iiat-es from. Agee and Huff
for different decay claa
sse s.
57
(1987)
'in~~~~~~~~~~I
'-
011.
1g
-
0
too
2t0
A4-.
a-
AII M IZON;~~~~~~~~~~~~~~~~~~~ ISIONEl(N
~~~~~~~~
Al~
Jf1ET
-C
L.
1;
ii
'o
o
~ ~ ~~~~~~~~
-
Figure 3. The fuel treated area is in the northwest corner of the monument, west of the chateau. The zones are various distances away from the chateau, and the transects are lines along which shrub layer cover and downed logs were measured. The small numbers scattered across the area are locations of snags.
Fire Behavior Estimates.
Data required to produce fire
behavior estimates through the computer program BEHAVE (Burgan and Rothermel 1984) were collected along each of the three transects (Figure 3) in the fuel manipulated area, plus one area of unmanipulated forest to serve as a comparison.
The program allows site-specific fuel models to
be built from data collected in the field, and when combined with environmental data (estimated fuel moistures, wind, etc.), fire behavior estimates are produced.
A fuel model
was built for each transect, and since the transect furthest from the chateau passes through two distinct fuel types, separate fuel models were built for the north and south ends of this transect.
Estimated changes in fuel parameters over
time were incorporated into the fuel models to produce estimates of current and future "worst case" fire behavior in the area.
RESULTS
Community Classification The forests of Oregon Caves are found roughly in the middle of the environmental gradients of the Siskiyou Mountains. Because the monument is relatively small, it is within only the upper part of the Mixed Evergreen Zone and mostly within the White Fir Zone of Franklin and Dyrness (1973; Figure 4). Another classification process besides the zonal one is 14
A 2000 ,, 0
1500 E E 1000 . 500
! LU
A.. Pro_
wtb
EAST
B
Mountain hemlock Be /9 /TanoaK
White fir
F~~~red fir \
\\
Douglas-fi r Ponderosa pine-White oak EAST 1-5
WEST Hwy 199
Figure 4. Schematic representations of major forest zones The zonal approach of Franklin and A. of the region. Dyrness (1973); Oregon Caves is primarily in the Mixed B. The plant association Evergreen and White Fir zones. approach of Atzet and Wheeler (1984); Oregon Caves is located near the boundary of the Tanoak, Douglas-fir, and White fir series.
15
based on plant series, named for the overstory species which would dominate the site in the absence of disturbance).
The
vegetation of Oregon Caves fits into the middle portion of the plant series ordination diagram for the Siskiyou Mountains
(Atzet and Wheeler 1983; Figure 4).
Neither the
lower elevation ponderosa pine - white oak nor the higher elevation Shasta red fir or mountain hemlock series are present at Oregon Caves.
Although the series are absent,
many of the species in those series do occur as secondary species at the monument: Shasta red fir and ponderosa pine, for example.
Definition of Plant Communities and Environmental Gradients. The results of the ordination and classification analysis using TWINSPAN and DECORANA are shown in Figure 5.
The
TWINSPAN results were used to objectively define communities.
The communities defined were as follows:
White Fir/Herb (n = 11); 2) Mesic White Fir/Douglas-fir 12)
1) (n =
; 3) Dry White Fir/Douglas-fir (n = 7); 4) Douglas-
fir/Oak (n = 13); 5) Oregon White Oak (n = 2); 6) Meadow (n = 4);
7) Alder
(n = 1).
The comparison of the plant community data to environmental variables
(elevation, slope,
and discriminant analysis.
etc.)
included both regression
The regression analysis, using
DECORANA Axis 1 score as the dependent variable and elevation,
transformed aspect,
16
and slope as independent
A
-I I
K-
Meadow I
White Oak
I
I
Alder
I
.
White fir! Herb
Douglas-f ir/Oak
-'Ii---I
Mesic White fir/Douglas-f ir
B
1
Dry White f ir/Douglas-fir
240
" 160
80
0
0
80
160
240
AXIS 1
Figure 5. A. Plant community types identified through the TWINSPAN analysis. B. Location of plots identified by plant community type on the first two axes of DECORANA ordination.
17
variables, yielded an adjusted r2 of 0.39.
This equation
explained only slightly over one-third of the variance associated with Axis 1 scores, and suggested that elevation, aspect, and slope are important but not complete descriptors of floristic variation at the monument.
Discriminant analysis produces functions which explain a certain amount of variability between groups in terms of other variables selected as possible "discriminating" variables.
The mesic and dry White Fir/Douglas-fir
communities were combined and the one alder stand plot removed to produce a cleaner analysis.
The analysis was fairly robust, with 63 percent of the plots correctly classified (the environmental variables followed the TWINSPAN groups 63 percent of the time).
The first function accounted for 85 percent of the variance explained by the analysis.
The variable weighting most
highly on this function was elevation.
The groups
responding most strongly to this function were the White fir/Herb, the Dry Douglas-fir/Oak and the Meadow.
The next
two functions (as many functions as variables are produced) accounted for only about 9 percent and 6 percent of the explained variance respectively, with cosine aspect weighted most heavily on the second function, along with the Meadow group. Slope and the Oregon White Oak community weighted 18
most heavily on the final function.
The White Fir/Douglas-
fir community did not respond strongly to any function.
These results suggest that a combination of elevation and aspect are most important in defining plant community types at Oregon Caves National Monument.
Plant Community Map and Key. above are mapped in Figure 6.
The communities described This map was created by
Figure 6. Generalized map of the plant community types of Oregon Caves. 19 --
Am
locating each plot on the map and drawing community boundaries in most cases as equidistant lines between plots. The map was field checked along the trail system and slight adjustments made to reflect community transitions where appropriate.
A key based primarily on tree characteristics is presented in Table 1.
It is not uncommon for keys based on limited In such
sampling to fail when applied in field situations. cases it is necessary to begin again in the key and
carefully evaluate which characteristic best fits the situation.
Once a community is keyed out, the field
characteristics should be compared to the plant community summaries in Tables 3-9.
These characteristics can also be
compared to other plant community classifications.
The most
comprehensive classification for the Siskiyous is for the Siskiyou National Forest (Atzet and Wheeler 1984).
The
Oregon Caves communities on the left (Table 2) can be compared to the plant associations for the Siskiyou National Forest on the right.
Community Descriptions
Each of the seven major plant communities at Oregon Caves is summarized in terms of its average tree density, basal area, height and percent cover (Tables 3-9).
Herb and shrub
average percent cover and constancy are also included.
20
All
Tatble 1.
Key to plant communities at Oregon Caves. . 2
Trees >10 m tall in stand
la
White fir >75% of basal area; understory dominated by herbs
2a
*
White Fir/Herb community
Other tree species >25% of basal area
2b
. 3
White fir > 50% of basal area and dominates density of all three tree strata
3a
(0-3 m,
3-10 m,
>10 m)
White fir-Douglas-fir/
.
mesic community White fir < 50% of basal area
3b
and is not dominant in top stratum
.
.
4
4a White fir < 25% of basal area; Evergreen hardwoods (including tanoak) codominant in understory; Douglas-fir may also be in 0-3 m stratum
.
.
.
.
.
.
Douglas-fir/Oak
community 4b White fir 25-50% basal area; white fir dominates density . in lower canopy strata
*
White fir-Douglas-fir/ dry community
No trees > 10 m tall; basal area trace to absent
lb 5a
Alder dominant .
5b
Alder absent 6a
6b
.
5
Alder community 6
Oregon white oak > 25/ha; . Sedum in understory
*
Oregon White Oak community
Oregon white oak lO0n
in/ha
in
238 0 0
140 0 7
288 14 0
64 2 T
38 28 4
4 1 1
0 14 0
0 7 7
7 7 0
T 6 2
12 16 26
1 1 1
#1=0-5%; 2=6-25%; 3=26-50%; 4=51-75%; 5=76-95%; 6=96-100%. Major Shrubs and Herbs Shrubs
Corylus cornuta Holodiscus discolor Rosa gymnnocarpa Symnphoricarpos albus
Herbs
(>10% cover or >20% constancy) Average Cover
Constancy
Percent
Percent
8.5 4.2 5.6 1.1
55 72 82 46
Average
Constancy
Cover Percent
Actea rubra Achlys triphylla Lathyrus polyphyllus Smilicina stellata Tiarella trifoliata Vancouveria hexandra Vicia californica Vicia Sp.
1-6#
Percent
21.6 22.6 14.1 15.1 T 4.4 15.9
46 82 37 73 27 36 36
13.4
18
26
'l'tbie 4.
Community summary of the Mesic White Fir/Douglas-fir community.
Major Trees
er ss
-
'lree Species
Tree Density/ha by Height Class
Basal Height of Cover Class Tallest Area
0-3m 3-lOn >lOm
m2/ha
277 8 8
Abies con color Acer glabrum Chamaecyparis lawsoniana Cornus nuttallii Lithocarpus densiflorus JPseudotsuga menziesii #1b0-5%;
2=6-25%;
0
8 0
3=26-50%;
Major Shrubs and Herbs
';hrubs
(>10% cover or >20%
constancy)
constancy Constancy -
Percent
lierberis nervosa ('orylus cornuta 1lolodiscus discolor kcosa gymnocarpa
Herbs
Actea rubra Achlys triphylla Adenocaulon bicolor Lathyrus polyphyllus Smilicina stellata Vancouveria hexandra Whipplea modesta
8.0 6.5 4.6 4.3
Percent 75 58 67 83
Average Cover
Constancy
Percent
Percent
5.6
51.9 1.9 18 .3
7.6 4.8 1.7
27
32 1 2 2 5 42
5=76-95%; 6=96-100%.
4=51-75%;
Average Cover
33 T T T T 28
187 0 0 0 0 82
212 0 0 8 0 8
m
100 33 75 58 33 25
1-6#
3 3
1
1 1 1 2
r
Table 5.
Community summary of the Dry White Fir/Douglas-fir community.
major Trees
Tree Species
Abies concolor Acer macrophyllum Arbutus menziesii Castanopsis chrysophylia Chamaecyparis lawsoniana Cornus nuttallii Pinus larabertiana Pseudotsuga rnenziesii Quercus chrysolepis #1=0-5%;
2=6-25%;
Tree Density/ha by Height Class
Basal Height of Cover Area Tallest Class
0-3m 3-10n >l0m
m 2 /ha
Shrubs
Berberis nervosa Corylus cornuta Holodiscus discolor Rosa gymnocarpa
Herbs
342 0 0 0 0 0 0 28
100 57 14 28 0 0 0 185
23 6 1 T 1 T 1 39
20 13 nd nd nd nd nd 38
3 1 1 1 1 1 1 4
28
0
0
T
1
1
5=76-95%;
6=96-100%.
(>10% cover or >20% constancy) Average Cover
Constancy
Percent
Percent
5.1 1.8 1.1
57 71 43
1.1
43
Average
Constancy
Cover Percent
Achlys triphylla Asarum sp. Polystichum munitum Smilicina stellata Tiarella trifoliata Trientalis latifolia Viola glabella
1-6#
114 14 0 0 0 0 0 0
3=26-50%; 4=51-75%;
Major Shrubs and Herbs
m
Percent
33
100
T
29
2.6
29
6.4 2.6 6.4 T
57 29 57 29
28
Table 6.
Community summary of the Douglas-fir/Oak community.
major Trees
Tree Species
Abies concolor Arbutus menziesii Calocecdrus decurrens Castanopsis chrysophylla Lithocarpus densiflorus Pinus attentuata Pinus lambertiana Pinus ponderosa Pseudotsuga menziesii Quercus chrysolepis Quercus garryana
Tree Density/ha by Height Class
Basal Height of Cover Area Tallest Class
0-3m 3-10m >l0m
mn2 /ha
m
206 0
125 25
88 13
8 5
21 15
2 1
31 0 81
6 0 25
0 0 6
1 T 1
4 8 12
1 1 1
0 12 0 25 225
0 0 0 69 56 6
6 6 6 106 19 0
1 1 1 31 2 1
35 51 49 32 13 3
1 1 1 3 2 1
*
#1=0-5%; 2=6-25%; 3=26-50%; 4=51-75%; 5=76-95%; *numerous very small root suckers
6=96-100%.
Major Shrubs and Herbs (>10% cover or >20% constancy) Shrubs
Berberis nervosa Pachistima myrsinites Rosa gyrnnocarpa Symphoricarpos albus
Average Cover
Constancy
Percent
Percent
11.3 1.8 4.2 1.2
Average
Herbs
77 31 54 46
Constancy
Cover
Achlys triphylla Chimaphila menziesii Chirnaphila umbellata Goodyera oblongifolia Polystichum muniturn
Percent
Percent
5.8 T 1.6 T T
46 23 23 23 23
29 ,I
1-6#
Table 7.
Community summary of the Oregon White Oak community.
Major Trees
Tree Species
Calocedrus decurrens Quercus g'arryana
Tree Density/ha by Height Class
Basal Height of Cover Area Tallest Class
0-3m 3-10m >l0m
in2/ha
m
80
0
0
T
T
1
*
60
0
5
4
3
5=76-95%; 6=96-100%. *many small root suckers Major Shrubs and Herbs
(>10% cover or >20% constancy)
Cover
Holodiscus discolor
Herbs
Percent
Percent
9
100
Average
Constancy
Cover Percent
Achillea millefolium Collomia grandiflora Graminae spp. Polystichum munitumi Sedum spathulifolium
1-60
Percent
9 7.7
100 50
7.7
50
7.7 43.75
50 50
30
Ta'ble 8.
Community summary of the Meadow community.
Major Trees ier Iss
TIree Species
Abies mnagnifica V~ithocarpus densiflorus Quiercus garryana
Tree Density/ha by Height Class
Basal Height of Cover Area Tallest Class
0-3m 3-10n >l0m
m 2 /ha
Shirubs
75
0
T
8
1
0
25
0
T
4
1
*
25
0
T
4
2
Average Cover
Constancy
Percent
Percent
.6 .6
25 25
Average Cover
Constancy
Percent
Percent
Achillea mnillefolium
Aq7astche urticifolia 1Kl'ymus glaucus Eri geron coul teri lheracleum lanatum .,,iussurea americana Veratrum viride
6=96-100%.
(>10% cover or >20% constancy)
Anielanchier alnifolia Arctostaphylos patula
Herbs
1-6#
75
#1=0 5%; 2=6-25%; 3=26-50%; 4=51-75%; 5=76-95%; *many small root suckers Major Shrubs and Herbs
in
.6
28 50 4. 5
17 . 1 7 .7
13 .9
31
25 75 100 50 75 50 75
Table 9.
Community summary of the Alder community.
Major Trees
Tree Species
Alnus sinuata #1=0-5%;
2=6-25%;
Tree Density/ha by Height Class
Basal Height of Covei Area Tallest ClasE
0-3m 3-l1in >l0m
m 2 /ha
0
0
1400
3=26-50%; 4=51-75%;
Major Shrubs and Herbs Shrubs
Ribes sp.
Herbs
(>10% cover or >20% constancy) Average Cover
Constancy
Percent
Percent
2.5
Average
100
Constancy
Percent
Percent
62.5 85 15.5 2.5 15.5
100 100 100 100 100
32
1-60
6
1
5=76-95%; 6=96-100%.
Cover
Achlys triphylla Agrostis alba Athyrium filix-femina Dicentra formosa Smilicina stellata
T
m
late laying snow, piled up in small wind eddy areas, precluding tree establishment due to shortened growing season. evening.
Deer are often seen grazing in these meadows in the Slopes are between 22 and 45 percent and tend
towards northerly aspects.
Alder.
The Alder community occurs along streams,
above 4500 ft.
especially
It is characterized by a thick growth of
small trees up to about 6 m tall
(Table 9),
and is an early
successional community largely a result of the 1964 flood which scoured the creek bottoms.
Under the canopy a variety
of herbs able to tolerate low light conditions are found. Redtop (Agrostis alba) introduced from Europe)
is a dominant grass (probably with vanillaleaf.
The one plot
sampled was on a 36 percent slope facing NNW at 4630 ft.
Fire History
The fire history of Oregon Caves National Monument is complex,
and these results do not capture that history in
the detail that it probably occurred.
An example of the
complexity of fire history in the Siskiyou Mountains is contained in Appendix B, a fire history of Kinney Creek. That study site is about 18 km east of the monument on a drier site at lower elevation.
The myriad fires identified
in 1916 occurring on the south facing slope (Figure 4 in the appendix)
simply could not be reconstructed using the
33 ,..
0Nq;6;z=
standing vegetation of today, and most were not capable of being identified in 1988 from stumps on the north side of the ridge.
Similar reconstructions in a natural area, where
stumps are primarily concentrated around the boundary, inevitably suffer the same loss of information.
Oregon
Caves National Monument is between 300 and 600 m higher elevation than Kinney Creek, and receives more annual and more summer precipitation (Froelich and others 1982, McNabb and others 1982) so fire is probably not as historically frequent as on Kinney Ridge.
This preface suggests,
however, that the following history is most likely a conservative reconstruction of the fire history of Oregon Caves. The oldest probable fire occurred ca. 1480-1490, about 500 years ago.
A Douglas-fir stump of that age was found just
southeast of the monument in a white fir/gooseberry habitat type, representing some opening of the canopy in order to provide growing space for this early seral species.
Along
the eastern boundary of the monument, several huge Douglasfirs and Port Orford cedars are present.
The Douglas-firs
were not aged, but may represent this same age class.
One
of the Port Orford cedars had three fire scars and the oldest scar was clearly prior to the mid-1500's; this tree appears to have survived the 1480's fire.
The "Big Tree"
along the monument trail is likely of this vintage, although rumors persist that the tree is much older.
As it is very
rotten and exceptionally large (it's growing in a seepage 34
area) the tree cannot be aged.
Because the cooler, upper
elevation areas all appear to have burned in this fire, the drier, lower elevation areas of the monument are assumed to have burned ca. 1480 (Figure 7).
This is well before the
time that European humans reached this area on foot, yet Haefner (1917) claimed that southern Oregon did not experience forest fires before "white man" reached the coast.
No fire activity was capable of being reconstructed for the 1500's.
Some fires likely occurred but have been obscured
by subsequent burning. 1650 (Figure 7).
The next fire reconstructed was ca.
Two stump dates from Douglas-fir were
found just southeast of the mcunument boundary.
A white fir
stump in a ravine, a sapling-sized tree at the time of the event, showed a significant growth release just after that time, and a Port Orford cedar along the eastern boundary had a fire scar. Fire evidence becomes more abundant by the end of the 1600's.
A fairly widespread age class of Douglas-fir became
established along the northern portion of the monument boundary during that time, suggesting a disturbance date of ca. 1695.
This age cohort of Douglas-fir (Figure 8)
suggests a moderate to high severity for the fire; a lot of Douglas-fir became established, and these trees were apparently filling in open space for about 30 years.
An
alternate explanation is two closely spaced fires, but this 35
Figure 7. Reconstructed fires of the last 500 years. The c.1480 and c.1650 fires were assumed to cover the entire monument as they left significant evidence in the wetter, cooler areas of the park. Other fires were reconstructed using the method shown in Figure 2.
C 1480-90
c 1650
36
C 1695
c 1730-40
37
c 1755
c 1775
38
c
1802
c1822
39
r- 0
-.- I - - ---I- --
-.-
- I I-II
c1826-29
C 1834-36
40
I
- ---
C1849-50
c 1875-76
41
-
c1890
I, i"
(
il
c1921
i.
l
42
0, 4
a, ~0
E1 zon
L 1695
1700
1730 1720 1710 1725 1715 1705 Year
Figure 8. A group or cohort of Douglas-fir that apparently became established after a c.1695 fire. This cohort had one of the longer regeneration tines after disturbance, possibly associated with a more intense fire.
was discounted due to the lack of any scars on the earliest established members of the cohort. In ca. 1730, a fire burned thE northwestern quarter of the monument (Figure 7).
The northern portion of this area
appears to have reburned in ca. 1755.
About 20 years later
(ca. 1775), most of the monument burned.
Another large fire
burned in ca. 1802, avoiding the eastern monument edge.
The
southwestern portion of the monument burned ca. 1822, and a mid-elevation band burned in the 1826-29 period.
Another
fire burned in 1834-36; eviderce of the fire in the southwestern portion of the monument may have been erased by later fires, which resulted in an awkwardly-shaped fishhook pattern for this fire.
43
---.-
...
___-_-________ ---
1
I .
In ca. 1849-50, a fire moved in from the northwestern corner of the monument but apparently did not spread too far within the present boundary (Figure 7).
Major fires were reported
for Kerby and Jacksonville in the 1865-67 period (Morris 1934) but apparently they did not reach Oregon Caves. ca. 1875-76, most of the western monument burned.
In
Similar
to fires in 1802, 1826-29, and 1834-36, the ridge up which the Big Tree trail winds served as the boundary for this fire.
In portions of this fire, particularly along the
central western edge of monument, this was a high severity fire.
In ca. 1890, another fire burned almost the same
area, but was of low severity across much of the monument, leaving occasional scars but not killing many of the young trees that regenerated after the ca. 1875-76 event. The last significant fire event identified at Oregon Caves occurred in 1921, after the monument was established and managed by the Forest Service.
No administrative records
have been uncovered that substantiate this event.
It may
have been somewhat unnoteworthy, occurring in a region that was burning frequently during this time (Hofmann 1917)
and
apparently underburning most of the forest it burned within the monument.
Since 1921, no major fires have started
within or entered the monument.
This has been the longest
fire-free period in more than 300 years. Fire return intervals calculated by century and forest community type show that fire has neither been a uniform 44
process in space nor time.
The time record (Table 10) is
biased in that earlier fires of low severity or spatial extent may have been missed.
Nevertheless, recurrent fire
has been a theme of the forests of Oregon Caves for over 500 years.
The 16th century is the only century of the last six
that fire did not play a significant ecological role.
The
increase in fire occurrence and frequency in the 19th century may be due to the stockmen/miner effect (Haefner 1917, Atzet and Wheeler 1982).
It may also reflect the
ability to more accurately identify more recent fires.
The
average natural fire rotation of 76 years is similar to other dry Douglas-fir forests west of the Cascades.
Natural
fire rotations of 80 and 100 years have been estimated for dry Douglas-fir forests in western Washington (Agee and Dunwiddie 1984, Agee and others in press), and for western Oregon (Morrison and Swanson in press, Teensma 1987). Fire has been a major influence on forest community species composition, structure, and function. for forest community types (Table 11)
The fire rotations indicate that the
white fir/herb type at the highest elevations in the monument has been less influenced by fire than the other types.
It appears to have acted as a barrier to fire spread
for many fires.
Douglas-fir is not common in this type,
which has a remarkably lush herbaceous cover during the summer which may retard the spread of all but the most intense fires until the herbs cure in autumn.
The presence
of an all-aged white fir forest, plus the presence of 45
-
Table 10.
Natural fire rotation for Oregon Caves by century.
Time Period
Area Burned
Proportion
ha
Natural Fire Rotation years
p
1400 -
1500
197
1.0
100
1500 -
1600
0
0
-
1600 -
1700
244
1.24
81
1700 -
1800
213
1.08
93
-
1900
576
2.92
34
1900 -
1989
86
0.44
204
1480 -
1989
1317
6.68
76
1800
', A
.".4 "I k
Table 11. Caves.
Natural fire rotation by community type at Oregon
Community Type
Area in Type ha
Area Burned ha
Proportion p
Natural Fire Rotation years
Douglas-fir/oak
45.1
386
8.6
60
Dry white fir/ Douglas-fir
42.0
315
7.5
68
Mesic white fir/ Douglas-fir
55.4
311
5.6
91
White fir/herb
35.9
192
5.4
94
8.8
53
6.0
85
Oak woodland
46
numerous windthrow mounds, suggest that wind is an important disturbance factor in this type.
The mesic white fir/Douglas-fir type, with more Douglas-fir, has slightly more frequent fire than the white fir-herb type, although the difference is not significant.
These two
types have the highest numbers of older trees (Figure 9). Fire has typically been of low to moderate severity, perhaps opening small patches which have generally regenerated quickly.
The ca. 1695 fire, with at least a 30 year
recruitment period, had the longest regeneration span found. The oak community type has slightly more frequent fire, and represents an average between the conifer types it separates.
The dry white fir/Douglas-fir type has burned
more frequently than the cooler and more moist conifer types,
and residuals from earlier fires are more sparse
(Figure 9).
Most of the trees are younger than the 1875-76
event, encouraged by growing space opened up by that fire, the 1890 fire, and the 1921 fire.
The southwestern portion
of the monument has a large cohort of white fir that established after the 1875-76 fire, with scattered Douglasfir and white fir residuals with charred bark.
The Douglas-fir/oak type has a similar fire frequency to the dry white fir/Douglas-fir type.
Many of the hardwoods in
this type have sprouted back from topkill after previous fires.
Douglas-fir is well-represented in all age classes,
47
-
---
MMMMMMM
White fir/herb 515
0
n n
. . .
FmarFKV
J
. . .
F 1-fl 44-n
A~
0
50
100
0
50
100
- . . . .
~%j
. . . .
200
300
200
300
5
0 a) 0)
10-
I,
50 -Q
ED
0
E z
-Jsil.
=T1
_
50
0
DryWhite fir/Douglas-fir
,
_
.
I
l, n
.
100
1AM
300
200
Douglas-fir/oak
10 5 0
0
25
50
75
100
125
150
200
250 300
Tree Age - 1988 Base El White fir
*
Douglas-fir
El Tanoak
IEl
E
Ponderosa pine
0
Sugar pine
[iD Pacific madrone El Oaks i Misc hardwoods
Shasta red fir LA Incense-cedar L
Port Orford cedar
alM Knobcone pine
Figure 9. Age structure of the four major forest communities of the monument. 48
I
responding after disturbance but also establishing underneath hardwood canopies.
The close proximity of these forest community types has an effect on fire return intervals.
In the North Cascades of
Washington, the interspersion of community types that typically burn either frequently or infrequently tended to lengthen fire return intervals for the communities with typically frequent fire and shorten them for communities with typically infrequent fire (Agee and others, in press). At Oregon Caves, the drier, lower elevation communities in this small monument probably have longer fire return intervals than in other areas where these types are more widespread; similarly, the higher elevation areas may have shorter fire return intervals than in areas where they are widespread, because of the absence of boundary fires from lower elevation moving into the community.
Where such
communities are interspersed cver very short distances as at Oregon Caves, a mixing of "typical" fire regimes is the result.
Forest stand development at Oregon Caves over the past several hundred years can be characterized as a series of moderate to low severity fires resulting in a typical multiaged stand, with age classes following the disturbances that opened the stand enough that regeneration occurred.
A stand
development sequence similar to that in Figure 10 (Agee in 49
-
Figure 10. A typical stand development sequence in the lower elevation, Douglas-fir/oak community in the presence of recurring fire. 50
I
press) may help to understand the current structure of stands at the monument.
Beginning after a stand replacement
fire, the Douglas-fir regenerating on the site may survive several moderate severity fires that thin the Douglas-fir, remove the understory white fir,
and topkill the associated
hardwoods such as madrone and tanoak.
Several reocurrences
of such fires will create a stand with several age classes of Douglas-fir, some of which are large, and an age class of Douglas-fir, white fir,
and hardwoods representing
regeneration after the last disturbance.
Large logs are
provided by Douglas-fir that have died and fallen after attack from insects, diseases, or the last fire. 250+ years,
At age
the structure of this stand may resemble the old
growth of more northerly Douglas-fir stands which have been undisturbed for 300 or more years, but have developed in a very different way.
Such stands will commonly be mixed with
others that have experienced a stand replacement fire event during one of the intermediate fires, so that the landscape has a patchy appearance.
The area around the chateau and
along the No-Name trail is such a mosaic of stands.
Fire Behavior in the Developed Area The area below the chateau was identified as a high fire hazard in the late 1970's, posing a substantial risk to fire control if a wildfire entered the monument from the west. fuelbreak was constructed west of the monument on Siskiyou National Forest land.
This treatment was augmented by a 51
I_
A
-I
fuel reduction project inside the monument during late 1982, covering the canyon bottom area from the chateau to the Small dead fuels were removed,
western monument boundary.
shrubs and understory trees were heavily thinned, and all residual trees were pruned.
Snags and large down debris
were left in place.
Shrub Regrowth.
Some shrub measurements previous to the
present effort were completed in 1986.
At that time, shrub
regrowth along the Forest Service fuelbreak was compared to the regrowth within the treated area at the monument as a "years since treatment" comparison, since the Forest Service fuelbreak was several years older.
The monument data were
collected along the north end of the 1988 transect 3 (Figure 3).
These data (memo by J. Agee to Superintendent, Crater
Lake, 12/18/86) suggested that the shrubs in the monument were growing faster than those on the fuelbreak.
In this
case, the "shrubs" are juvenile forms of three tree species, which often assume a shrubby, multi-stemmed habit when sprouting after disturbance by fire or cutting.
Both shrub
density (11000/ha [4450/ac] versus 3100/ha [1250/ac]) and height growth were higher on the monument transect than the nearby Forest Service fuelbreak.
Generally, madrone grew
the fastest, followed by tanoak, with canyon live oak the shortest in any given year since treatment.
p 52
I
-
In 1988, cover and height of shrubs were measured along the three transects (Table 12).
Total shrub/small tree cover
along transect 1 is now 11.2 percent, while on transect 2 it is 9.4 percent,
and on transect 3 it is 21.9 percent.
An
average height, weighted by relative cover of the shrub species, (2.0 ft),
for the three transects is 0.6 m (1.9 ft), and 0.5 m (1.8 ft)
0.6 m
for the three transects.
These
data are incorporated into the fuel models built for fire behavior simulation.
Shrub regrowth over time for the three major species 11)
(Figure
as measured early in 1988 showed results similar to the
1986 measurements: madrone was growing the fastest and canyon live oak was growing the slowest in height.
Diameter
of tanoak and canyon live oak clumps was predicted well by diameter of the stump left after the fuel treatment;
large
diameter stumps resulted in broad shrub clumps (Table 13). Diameter of the stump was not useful in predicting clump diameter of the madrone sprouts.
Stump diameter was less;
useful in predicting clump height
(Table 13).
These resultt
are less successful than those of Tappeiner and others (1984),
who looked at sprout recovery after clearcuttin(rvt
ml
burning; probably the influence of overstory canopy at Oregon Caves has an effect on subsequent growth in addi to stump diameter.
ik
Stumps in relatively open situatiuiin
will sprout more vigorously than those that remain shaded.
53
o
1 11
ttg y
Table 12. Cover and height of shrub layer vegetation in fueltreated area, 1988.
species
Cover %
Arbutus mnenziesii Berberis nervosa Castanopsis chrysophyll1a Corylus cornuta Holodiscus discolor Lithocarpus densiflorus Pseudotsuga menziesii Quercus chrysolepis Rhus diversiloba Ribes spp. Rubus spp. Symphoricarpos mollis Vaccinium parvifolium
Table 13.
Ht
Cover
Ht
Cover
Ht
ft
%
ft
%
ft
2.3
0.3
3.0
0.3
2.3
4.5
0.4
4.8
3.9
0.2
2.8
1.8
0.3
0.3
2.7
0.5
0.7 2.5
1.1 6.0
0.8
1.1
0.4
1.1
0.2
0.9
2.6
2.2
0.4 9.1
1.2 2.4
3.7
2.1
0.1
3.0
0.4 0.6 0.1
2.0 1.0 0.8
0.1
1.0
Equations to predict plant clump diameter and height from stump diameter. All units in cm.
73.8 + 4.18
(1988)
Diameter
(1988)
=
Height (1988)
=
Diameter (1988)
=
Diameter (1988)
r2
= 52.5%
(Stump Diameter) r2
55.9 + 8.01
172 =
79.4%
=
-
117
2.69 -
(Stump Diameter) r2
0
=
(Stump Diameter) r 2
0.48
= 0
Quercus chrysol epis
Canyon Live Oak (1988)
(Stump Diameter)
Arbutus menziesii
Pacific Madrone
Height
Transect 3
Lithocarpus densiflorus
Tanoak Height
Transect 2
Transect 1
66.0 + 2.17 =
(Stump Diameter) r 2
55.9 + 6.46
54
=
(Stump Diameter) r 2
24.5% =
74.4%
Percent moisture content (dry weight) of leaves at Table 14. Oregon Caves National Monument, L989.
2.1 3.0 2.0 1.0 0.8 1.0
N-few
Old
95
96
81
19 5
1 33
151
51
89
97
79
90
1 96
114
18 1
14 0
N-ew
Ol d-
Tanoak
203
Pacific madrone Canyon live oak Douglas-fir
Pacific ..a madrone 0 I
z
)Canyon live oak
-j
0 w
1982
83
85 84 YEAR
86
1987
madrone, tanoak, and canyon livE' oak.
55
U
1989
Age of leaves
Age of leaves
ft
0.4 0.9 2 .2 1.2 2.4
August 26,
1989
July 20,
Plant Species
Fuel moisture for these shrubby understory clumps is fairly low by late season.
Results of duplicate samples from three
clumps of each species are shown in Table 14.
Moisture
content of new foliage tends to decline more rapidly than that of older foliage.
The average moisture content of
tanoak leaves was below 100 percent for late August. Pacific madrone retained high moisture in new leaves, but older leaves with low moisture were relatively senescent and either wilting or dying.
Canyon live oak at both sampliong
dates had low foliar moisture, with older foliage having higher moisture than new foliage.
Douglas-fir saplings had
higher avergae foliage moisture in late season than the other species.
These late season values are associated with
annual and seasonal rainfall, which varies from year to year.
1989 was an average year, so foliar moisture was
probably not at extreme values it might be in drought years. Therefore a lower average foliar moisture value of 70 percent was used in the fire behavior simulations produced with the BEHAVE model.
Snags and Downed Logs.
Snags and downed logs are common
below the developed area.
Some of the downed material is
from windthrow, partly a result of the expansion of the parking lot.
The forest stand below the parking lot has
gradually been opened up by individual or group windfalls. The predominantly old growth Douglas-fir (240-270 years old)
56
is heavily infested with dwarfmistletoe.
In combination
with drought impacts during the late 1980's and disease
(Phellinus pini, red ring rot), substantial breakup of the stand has occurred and will continue into the future.
The distribution of snags within the fuel-treated area is shown in Figures 3 and 12.
Most of the snags are Douglas-
fir and are less than 1 m in diameter (Figure 13). range up to 50 m tall below 15 m in height.
(Figure 14),
They
but roughly half are
Over 2/3 of the snags are in the
zones between 100 and 200 m removed from the chateau; few are in the closest (0-50 m) zone.
About 2/3 of the snags
have broken tops; the distribution of sound versus brokentopped snags by zone is shown in Figure 15 by zone is:
Zone 1, 5.37/ha (2.17/ac);
(a-e).
Density
Zone 2, 11.81/ha
(4.78/ac);
Zone 3, 17.08/ha (6.91/ac); Zone 4, 19.25/ha
(7.80/ac);
Zone 5, 10.62/ha (4.30/ac).
The density is
higher than normally found in old-growth Douglas-fir becau : the stand is in the midst of breaking up from the factors summarized above. t/ha
(9.25 t/ac)
The mass of standing snags is about 20 for the area as a whole.
The significance of snags to fire behavior is that fire either carry up the dead exterior of a snag into the crown or the punky tops (particularly for broken-topped snags) be easily ignited by spotting firebrands.
Such snags.th-
become sources for further firebrands that will blow
57
'
1,
-
Snags Below the Cli atea u 30B Percent of Snags Z ~~~~~~~~~I
I -I
50
106 150 200 50 Meter Distance
250
Figure 12. Percentage of snags in different distance zones from the chateau (50 = Zone 1 to 250 = Zone 5) within the fuel treated area. Diameter Distribution
60+ Number 40+ 26+
0-50
SO-iRO 100-150 Size (cm)
Figure 13. Distribution of snags by diameter class within the fuel treated area. Snag
Per cent
Height
. .1 .1
6 5 10 152OZS30 3540 45 5 m Heighit Class Figure 14. Distribution of snEags by height classes within the fuel treated area. 58
k
Condition of Snag Tops
ZONE 1
1.
El Broken Top
Number
*
0. 0
Sound Top
10 20 30 40
Height Class (meters) ZONE 2
Condition of
Snag Tops
ZONE 3
Condition of Snag Tops 3'
2! 21 Number 1' 11
Number
0 10 20 30 40 Height Class (meters)
ZONE
4
Condition of
0 10 20 30 40 Height Class (meters)
Snag Tops
ZONE 5
Condition of Snag Tops
40 m03
Numberm
Number
3 2 11
0 10 20 30 40 Height Class (meters)
i 0 10 20 30 40 Height Class (meters)
Figure 15. Condition of snag tops within the fuel-treated area by zone (distance from chateau) and height class.
59
Snags are dangerous to cut at any time, but are
downwind.
particularly hazardous to fall when burning.
Downed logs were measured along the three transects; the mass by decay class is shown in Table 15.
Most of the mass
is concentrated in the areas removed from the chateau along transect 3.
Logs are not primarily vectors for fire spread,
but have substantial impact on heat release once they ignite.
They can also be barriers to fireline construction,
which is particularly significant under emergency situations.
Fire Behavior.
The intent of the 1982
fuel manipulation was
to lessen the hazard of fire In the area west of the chateau.
One means of assessing this hazard reduction is
through fire behavior simulations using the computer program BEHAVE, using actual fuel conditions in the treated area and
Table 15.
Biomass of downed Logs in fuel treated area below the chateau, tons/ha (tons/ac).
Number
1
Class
Decay
Transect
3-4
1-2 1 (0.4)
5
Total
36
(16)
0 (0)
37
(17)
2
14
(6)
26
(11)
0 (0)
39
(17)
3
49
(22)
101
(45)
3 (1)
153
(68)
60
comparing that to areas that remain untreated.
Note Iit,
these simulations deal only with surface fire behavior crowning or spotting.
Under "worst case" conditions,
ntt !
l
with predicted flame lengths below 4 feet are often Capih1 of being controlled with hand tools,
and this is the
criterion used here for identifying areas for retreatment
For the purposes of this simulation, hr,
fuel moistures for lx
10-hr, and 100-hr timelag fuels were varied from "low"
values of 3,4,
and 5 percent,
to "medium" values of 6, 7,
and 8 percent, respectively; woody and herbaceous fuels wot'e assumed to have 70 percent fuel moisture; and slope was sot at 20 percent. windspeeds
In this "worst case" scenario, midflame
(usually lower than the local winds)
were varied
from 4 to 12 mph.
Individual models were built from data collected on transect 1 (Figure 3),
transect 2, and each of the north and south
aspects of transect 3.
Untreated fuels were assumed to
mimic standard NFFL Model 10
"Timber with litter and
understory".
Predicted flame lengths for wildfires burning in untreated fuels and the treated areas (Figure 16) "low" or "medium" fuel moisture,
indicate that under
fires occurring in
untreated fuels would be very difficult to control, especially at higher windspeeds. 61
After 7 years of regrowth
14 12
2
co 2
~T~Pg4SFC-T3
Low
O TRANSECTS:0 1,2, and 3a(MeJ 12
8
4
M idf lame Wind (mphj Simulated fire behavior for untreated and Figure 16. Transect locations treated fuels around the developed area. are shown in Figure 3. Transect 1 is nearest the chateau, Transect 2 across the canyon fron the ranger station, and Transect 3 nearest to the monument boundary (3A is the south side of the creek,
3B is the north side).
"Low" and
The output for Transect 3b "Medium" refer to fuel moisture. (not shown) is between the "Low" and "Medium" NFFL 10 model output.
62
1
in the treated areas, fire behavior is moderate to low, most cases capable of being fought with hand tools.
in
Only min
the south-facing aspect of the treated area (below the entrance sign) is fire behavior predicted to mimic untreated fuels (Transect 3b, Figure 16).
These results suggest that no retreatment is now needed in the area manipulated in 1982, except for the slope below th). entrance sign.
Over time, the other areas may regrow enoluqh
to warrant retreatment, but not for at least another five years.
Hazard to the chateau is still high, for any fires moving into the treated zone, although capable of being controlled on the ground, will possibly move up one or more of the snags in the area, or catch fire from a spark blown from downcanyon (typical midafternoon wind pattern).
In this
event, embers from the burning snag(s) will likely blow upcanyon towards the chateau.
The chateau now has a
sprinkler system installed that will help keep it from catching fire.
Newer technology using foam, which was
effectively used at Yellowstone to protect structures, might be considered in the future as an alternative to the roof sprinkler system.
If used at the same time, the sprinkler
will wash off the foam.
63
-i
-_-__
q r
-1
- I -
_ __-
. __ -
-
- __1 11
-_
- I
11
II
I
I
-
__ -
ACKNOWLEDGMENTS
This project was supported under NPS Cooperative Agreement CA-9000-8-0007 Subagreement 8, between the National Park Service and the University of Washington. the park staff,
Assistance from
especially Ranger Larry Cosby and Chief
Ranger Terry Darby,
is appreciated.
The cooperation of the
Canteen Company of Oregon in providing room and board for us at Oregon Caves is gratefully acknowledged.
LITERATURE CITED
Agee, J.K. in press. Fire history of Douglas-fir forests of the Pacific Northwest. pp. -- In: Wildlife and Vegetation of Unmanaged Douglas-fir Forests. USDA For. Serv. Gen. Tech. Rep. PNW-xxx. Agee, J.K., and P.W. Dunwiddie. 1984. Recent forest development on Yellow Island, Washington. Canadian Journal of Botany 62: 2074-2080. Agee, J.K., and J. Kertis. 1987. Forest types of the North Cascades National Park Service Complex. Canadian Journal of Botany 65: 1520-1530. Agee, J.K., and M.H. Huff. 1987. Fuel succession in a western hemlock/Douglas-fir forest. Canadian Journal of Forest Research 17: 697-704. Agee, J.K., M. Finney, and R. de Gouvenain. in press. Forest fire history of Desolation Peak, Washington. Canadian Journal of Forest Research. Atzet, T., and D. Wheeler. 1982. Historical and ecological perspectives on fire activity in the Klamath Geological Province of the Rogue River and Siskiyou National Forests. USDA For. Serv., Pacific Northwest Region. Portland, Or. 16pp.
64
U
Atzet, T., D. Wheeler, J. Franklin, and B. Smith. 1983. Vegetation classification in southwestern Oregon - a preliminary report. Oregon State University FIR Report 4(4): 6-8. Atzet, T., and D. Wheeler. 1984. Preliminary plant associations of the Siskiyou Mountain Province. USDA Fore:;t Service, Pacific Northwest Region. Portland, Or. 315p. Barrett, S.W., and S. Arno. 1988. Increment borer methods for determining fire history in coniferous forests. USDA For. Serv. Gen. Tech. Rep. INT-244. Brown, J.K. 1974. Handbook for inventorying downed woody material. USDA For. Serv. Gen. Tech. Rep. INT-16. Burgan, R., and R. Rothermel. 1984. BEHAVE: fire behavior prediction and fuel modeling system - FUEL subsystem. USDA For. Serv. Gen. Tech. Rep. INT-167. Franklin, J.F., and C.T. Dyrness. 1973. Natural vegetation of Oregon and Washington. USDA For. Serv. Gen. Tech. Rep. PNW-8. Portland, Or. Froehlich, H., D. McNabb, and F. Gaweda. 1982. Average annual precipitation in southwest Oregon, 1960-80. Oregon State Univ. Ext. Serv. Misc. Pub. 8220. Corvallis, Or. Haefner, H.F. 1917. Chaparral areas on the Siskiyou National Forest. Proc. Society of American Foresters 12: 82-95. Heinselman, M. 1973. Fire in the virgin forests of the Boundary Waters Canoe Area, Minnesota. Quat. Res. 3: 329382. Hill, M.O. 1979. TWINSPAN - a FORTRAN program for arranging multivariate data in an ordered two-way table by classification of the individuals and attributes. Cornell Univ. Ithaca, NY. Hofmann, J.V. 1917. The relation of brush fires to natural reproduction: Applegate Division of the Crater National Forest. USDA For. Serv., Wind River Expt. Sta., Washington. 32 pp. McNabb, D., Froehlich, H., and F. Gaweda. 1982. Average dry season precipitation in southwest Oregon, May through September. Oregon State Univ. Ext. Serv. Misc. Pub. 8220. Corvallis, Or. Morris, W.G. 1934. Forest fires in Oregon and Washington. Oregon Historical Quarterly 35: 313-339.
65
-I
Fire history in two Morrison, P., and F. Swanson. 1989. forest ecosystems of the central western Cascades of Oregon. USDA For. Serv. Gen. Tech. Rep. PNW-xxx. An expression for the effect of aspect, Stage, A. 1976. For. Sci. 22: 457slope, and habitat type on tree growth. 460. Tappeiner, J., T.B. Harrington, and J. Walstad. 1984. Predicting recovery of tanoak (Lithocarpus densiflorus) and Pacific madrone (Arbutus menziesii) after cutting or Weed Science 32: 413-417. burning. Fire history and fire regimes of the Teensma, P.D.A. 1987. Ph.D. Dissertation, central western Cascades of Oregon. Eugene, Or. 188p. University of Oregon. Vegetation of the Siskiyou Mountains, Whittaker, R.H. 1960. Ecological Monographs 30: 279-338. Oregon and California.
66
Appendix A. List of Plants in Oregon Caves Community Types. This list is not a complete flora, but lists the plants identified on all plots in this study and the most likely communities within which they are found. A key to the numbers in the left column is found at the end of the appendix. Community Type*
Scientific Name
Common Name
Trees 1,2, 3,4 1,6 1,2 1,3 7 3,4 1,2,3,4,5,6 3,4 2,3 2,3 2,3,4,6 4 3,4 4 1,2,3,4 3,4 4,5,6
Abies concolor Abies magnifica Acer glabrum Acer macrophyllum Alnus sinuata Arbutus menziesii Calocedrus decurrens Castanopsis chrysophylla Chamaecyparis lawsoniana Cornus nuttallii Lithocarpus densiflorus Pinus attentuata Pinus lambertiana Pinus ponderosa Pseudotsuga menziesii Quercus chrysolepis Quercus garryana
white fir red fir Rocky Mountain maple bigleaf maple slide alder Pacific madrone incense-cedar chinquapin Port Orford-cedar dogwood tanoak knobcone pine sugar pine ponderosa pine Douglas-fir canyon live oak Oregon white oak
Amelanchier alnifolia Arctostaphylos patu.'a Berberis nervosa Corylus cornuta Holodiscus discolor Pachistima myrsinitos Rhus diversiloba Ribes binorniniatum Ribes lobbii Ribes spp. Rosa gymnocarpa Rubus ursinus
western servicel), greenleaf manzanl.i Oregon grape hazelnut creambush ocean:.p).i Oregon boxwood poison-oak trailing gooc;L-i i gummy goosebc'Lr gooseberry baldhip rose Pacific blit. Hi'i y blackberry common snos'1wti y creeping !-,n iaI big huc} Iftl't 'iy
Shrubs 6 4,6 2,3,4 1,2,3 1,2,3,4,5 4 4 1
1,4 1,7 1,2,3,4 2 3 1,2,4 4 1
Rubus spp.
Symphoricarpos albus Symphoricarpos mollis Vaccinium membranaceum
Herbs, Ferns 5,6 1,2,3,4,7 1,2,3
Achillea millefolium Achlys triphylla Actea rubra
A-1 ---
yarrow vani I l It hi! banehe r
1,
'
Community
Scientific Name
Common Name
Type* Herbs, 1, 2 6 7 4 4 4 4 7 4 2 1,4 4 2 6 4 4 1 5 5 7 1, 2 2 4, 6 6 4 4 1,3 1, 2 4, 6 3, 5 3 ,4 6 6 1 1, 3 ,4 1, 2 4 6 6 2 4 1, 2 3 ,4, 5 1, 2 ,4 6 6
Ferns (Contd) Adenocaulon bicolor Agastache urticifolia Agrostis alba Aren aria macrophyll a Arnica spp. Asarum Hartwegii Aster spp. Athyrium filix-femina Boschniakia Hookerii Bromus pacifica Bromus spp. Gailamagrostis spp. Campanula rotundifo-lia Castilleja affinis Chimaphila men ziesii Chimaphila umbellata Circaea alpina Collomia grandiflora cryptogramina cris pa Dicentra formosa Disporum Hook en Disporum spp. Elymus glaucus .Erigeron coulteri Eric gonum umbella turn Fragaria californica Fragaria platypetela Galium asperrimum Galium triflorum Galium spp. Goodyera oblongifolia Hacklia jessicae Heuchera spp. Hieracium albiflorum iris chrysophylla Lathyrus polyphyllus Linnaea borealis Luzula comosa Madia spp. Melica subulata Montia sibirica Phlox adsurgens Polystichum munitum Pteridium aquilinum Rumex salicifolius Saussurea americana A-2
trail plant nettle-leaved horse mint redtop bigleaf sandwort arnica Hartweg's wild ginger aster lady fern ground cone Pacific brome brome reedgrass Scotch bellf lower Indian paintbrush little prince's pine common prince's pine enchanter's nightshade large-flowered collomia rock brake Pacific bleedingheart Hooker' s twisted-stalk twisted-stalk blue wildrye Coulter's fleabane sulphur buckwheat California strawberry broad-petaled strawberry rough bedstraw sweetscented bedstraw bedstraw rattlesnake plantain blue stickseed a lumroot white-flowered hawkweed slender-tubed iris leafy pea twinf lower woodrush tarweed Alaska oniongrass miner's lettuce periwinkle phlox sword fern bracken fern willow dock American sawwort
-- ___
- 4
-
- I
community Type* Herbs,
--
-
Scientific Name
Sedum spathulifolium Senecio triangularis Smilicina stellata Tiarella trifoliata Trientalis latifolia Trillium rivale Vancouveria hexandra Veratrum viride Vicia californica Viola glabella Viola spp. Whipplea modesta
*Community Reference: 1 = White Fir/Herb 2 = Mesic White Fir/Douglas-fir 3 = Dry White fir/Douglas-fir 4 = Douglas-fir/Oak 5 = Oregon white oak 6 = Meadow 7 = Alder
A-3 I
- 11
I
.
Common Name
Ferns (Contd)
5 6 1,2,3,4,7 1,3 1,2,3,4 3 1,2 4,6 1,3,4 2,3 1,3 2,4
-
- ,I
broadleaf stonecrop arrowleaf groundsel false solomon's seal foamflower western starflower Oregon trillium inside-out flower green false hellebore California vetch stream violet violet whipplevine
APPENDIX B A VEGETATION HISTORY OF THE KINNEY CREEK AREA, ROGUE RIVER NATIONAL FOREST, OREGON James K. Agee Winter 1990 The early part of the twentieth century heralded the beginning of modern forest management in the United States. Forest fire was, literally and figuratively, the spark that mobilized local cooperatives and encouraged early state and federal forest fire legislation. As modern forest management developed, one of its major enemies was wildfire in the forest. The Forest Service took a lead role in opposing the use and misuse of fire in the forest (Agee 1989). In southwestern Oregon, the role of fire was not well understood in the early twentieth century. In 1916, the Forest Service assigned Julius Hofmann, Director of the Wind River Experiment Station in southern Washington, to survey the situation in the Applegate Division of the Crater National Forest (which later became the Rogue River National Forest). Hofmann's report, published early in 1917, concluded that all the brushy areas of the Applegate region were once timbered, and that the timber was destroyed by repeated burning. Protection of tree reproduction was essential if reforestation was to occur. An original carbon copy of the report was located in the Forest Resources Library at the University of Washington (except for three charts illustrating transect data). The report is historically significant in three respects: it reflects the bias present in almost all the early western forest fire bulletins against any benefits of fire, it contains useful narrative material about the Applegate area, and it contains an excellent, and partially reproducible, photographic essay of the Kinney Creek area. The report's introduction suggests the purpose of the study is to evaluate whether "light burning or periodic burning is desirable for timber production, watershed protection, or range management". As with most other early reports on forest fire, periodic burning is not differentiated from light burning: the former may be low or high intensity fire, while the latter is low intensity only. Three of the locations near Kinney Creek (Figure 1), originally photographed in 1916, were rephotographed in 1988 from similar camera points (Figures 2, 3, and 4). In 1916, there was only a trail; in 1988, there was a road traversing the slope along a slightly different route. Tree growth since 1916 obscured some of the possible original vistas. B-1
I
The south-facing slope of Kinney Creek in 1916 is shown in Figure 2A, with its 1988 counterpart below (Figure 2B). Shallow soil areas (arrow at left center) on the far slope are remarkably stable over the 70 year period. The texture of the far slope appears similar between 1916 and 1988. There appear to be a few more large trees in 1916 on the right (east) end of the slope, and a few more mature trees to the left (west) in 1988. These are likely to be Douglasfir (Pseudotsuga menziesii) with some ponderosa pine (Pinus ponderosa). The background of the July-August 1916 photograph (2A) is hazy, suggesting that fires were active somewhere in the region. The right portion of the foreground slope is open and brushy; this is likely the result of an earlier fire. In 1988 (2B) much of this slope is obscured by tree growth. Figures 3A-3B show an area slightly upstream from Figures 2A-2B. The road that approaches Kinney Peak leaves the Kinney Creek canyon bottom just off the lower right of Figure 3B. In 1916 (Figure 3A) recent fires had burned over the slopes, leaving Douglas-fir residuals along the ridgetops, in the ravines, and along the west-facing (left) slope of the spur ridge in the center of the photograph. By 1988, considerable coniferous forest regeneration had occurred across most of the landscape. In areas having a mottled texture in 1916, indicating exposed soil and possible periodic slope instability, Pacific madrone (Arbutus menziesii) has been more successful. By far the most impressive photograph comparison is Figure 4A-4B, showing the area along Kinney Ridge looking southeast. This area was repeatedly burned, with numbers on Figure 4A corresponding to fire dates of: 1 = 1915; 2 = 1914; 3 = 1910; 4 = 1897; 5 = 1886; and 6 = 1854.
Hofmann
notes that the repeated burning and complex mosaic of burned and unburned areas makes reconstruction of the events very difficult in this area. Closely-spaced burns have favored those species that can reach maturity quickly, such as knobcone pine (Pinus attentuata). Hofmann did not indicate how he was able to reconstruct the events of the previous 70 years. A brief ground check of this area in 1988 indicated that Hofmann's chronology would be very difficult to reconstruct in 1988. Three Douglasfirs were increment cored in Hofmann's area 5 (Figure 4A). The dates estimated for germination (which may be 1-3 years in error) were 1889, 1901, and 1905. These dates could represent continuous reproduction after a single event in 1886 or pulsed regeneration after the 1886 fire and possible underburns in 1900 and/or 1904. A canyon live oak (Quercus chrysolepis) cored in the area appeared to have sprouted around 1910, the year of one of the fires in the area. In area 4 (Figure 4A), listed by Hofmann as having burned in B-2
1897, two Douglas-firs cored were estimated to have germinated in 1884 and 1899; the 1884 tree must have been missed by the 1897 fire. A dwarf variety of Oregon white oak (Quercus garryana) was cored and showed a sprout date of 1862 within an area reportedly burned in 1910; this plant may have been missed by this fire, as the plant was low to the ground, or perhaps was scorched but resprouted a new crown and shed any charred bark. From the tree data collected, reconstruction of the fire events would not have been possible. Fire scars would have helped, but there were no obvious fire scars throughout this area. It appears that most trees either were killed (at least back to the ground for sprouting hardwoods) or were missed by the fires on this south-facing slope. On the adjacent north-facing slope of Kinney Creek (arrow in Figure 4B), a recent clearcut allowed fire event reconstruction from scars on stumps. This area was cut in 1985 (Richard Marlega, District Ranger, Applegate Ranger District, Rogue River National Forest, personal communication). Annual rings were counted on stumps back to the edges of scarred tissue, and the year of the fire could then be estimated. For example, a tree with 100 annual rings between a scar and the bark would have a fire date of 1985
-
100 = 1885.
Possibly eight fires have burned this
areas since about 1750 (Table 1); apparently none of the fires identified by Hofmann burned very far into this northfacing stand of trees. Because these dates were made on field counts of stumps, the actual year may vary slightly from that listed. Two significant conclusions can be made from these data. First, this mature stand of Dcuglas-fir underburned about every 15 years between 1760 and 1860, a surprisingly high frequency for this Douglas-fir/Oregon grape habitat type. This high fire frequency may reflect the fact that this is a small patch of mesic forest surrounded by drier low elevation types with ponderosa pine becoming codominant (e.g., Agee and others, in press), and near a south-facing slope (Figure 4A) that burned repeatedly after 1860 and very likely before 1860 as well. The second conclusion is that Hofmann's implication that fires were a product of modern human activity may not be true. Such allegations were also made by Haefner (1917) who claimed on the adjacent Siskiyou National Forest that after white man reached the area, Indians, miners, stockmen, and hunters had so increased fire frequency that little trace was left of virgin stands in many areas. The fire frequency in the south-facing area of Figure 4A between 1850-1920 was about 12 years, not so different from the 1760-1860 fire frequency of 16 years on the north-facing slope, which was B-3
a
-u
measured on a much smaller area and would thus probably be a more conservative estimate of fire frequency. Whether or not fire was historically frequent is surely no precise guide to fire strategies in today's complex Douglas-fir forests are difficult to management world. underburn with generally small prescription windows; air quality constraints are making those windows even smaller. Intense fire can eliminate Douglas-fir and favor "endurer" species (e.g., Rowe, 1981) such as madrone or canyon live oak, which sprout, or "evader" species like knobcone pine Douglas-fir is a which store seed in serotinous cones. "resister" species that because of its thick bark can survive low to moderate intensity fires; the data in Table 1 suggest that strategy was effective for Douglas-fir over the Fire mimicked a last 250 years in the north-facing stand. series of heavy shelterwood operations, with many of the larger stems being left and the associated hardwoods topHowever, in patches where fires were intense, all killed. the trees may have been killed, and madrone and oak or brush species may become dominant for many decades. Literature Cited Wildfire in the Pacific West: a brief Agee, J.K. 1989. pp. 11-16 In: history and its implications for the future. Proceedings of the Symposium on Fire and Watershed USDA For. Serv. Gen. Tech. Rep. PSW-109. Management. Agee, J.K., M. Finney, and R. deGouvenain (In press). Forest fire history of Desolation Peak, Washington. Canadian Journal of Forest Research. Chaparral areas on the Siskiyou Haefner, H.F. 1917. Proc. Soc. Amer. Foresters 12,1: 82-95. National Forest. Concepts of fire effects on plant Rowe, J.S. 1981. In: Wein, R.W.; MacLean, D.A. species. individuals and northern circumpolar ecosystems. in fire The role of (eds.) 322p. Sons. and New York: John Wiley
B-4
-
Table 1. Estimated fire dates from Kinney Creek clearcut (Unit #10). All trees are Douglas-fir and cut date is assumed to be 1985. Area surveyed was approximately 5 acres. Tree Number
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Fire Date(s) 1857
1841
1825 1825 1831
1807
1790?
1747g 1780g
1856
1778
1748g
1839 1794
1766g 1773g
1807 1795 1798 1794
1839
1764g
1825 1825
1764g 1765g
1797
1916g
Estimated Fire Dates* 1915
1856
1839
1825
1807
1795
1778
1763
1746
? = rings not clear
g = estimated germination date * Estimated fire dates from field counts are always subject to some error but are probably within a year or two; firedates estimated from germination dates (column on left and two columns on right) are to be interpreted as the latest date possible (e.g., 1763 might be 1760 or earlier but not 1765).
B-5
-------
___
Figure 1. Location of the Kinney Creek area in the eastern Siskiyou Mountains of Oregon.
A
B
Figure 2. The Kinney Creek landscape in 1916 and 1988, from the north-facing slope looking northeast. Arrow in (A) indicates shallow soil area. B-6
- .
A
Figure 3. Another paired set of photographs 1916-1988, in the Kinney Creek watershed. VLew is from the north-facing slope to the north.
B-7 WO
U.
,
I
n
,
A: Aid is ^*>^
+¢I-
-
-A~l%
-I
tQWas
.
':
and
Figure 4. A view from the Kinney Ridge area looking southeast: A: 1916, by J. Hofmann. B: 1988. Numbers in A refer to fires: 1886; 6 = 1854.
1
=
1915; 2
B-8
=
1914; 3
=
1910; 4
=
1897;
5
=
-
