35 Year Ditch-Creek Burn study

Robin Castell, Sara Koffi

Question?

• A Discussion with Mike Posthumus brought up the topic of the Ditch Creek Fire in 1974

• Has the sagebrush/bitterbrush community affected by the Ditch Creek Fire of ’74 fully recovered?

Introduction

• August 13th, 1974: Ditch Creek Fire occurs

• 1974-1979: Teton Science Schools performed a 5 year continued study of the burn; it was revisited in 1988

• 2009: 35 years later the Ditch Creek Fire study was reopened to record the long-term effects on its surroundings

Hypothesis

• A study, conducted in Clark Country, Idaho suggests a 30 year recovery rate for Sage brush (Harniss and Robert, 1973) - As a result, our hypothesis is the following:

• The sagebrush/bitterbrush affected by the Ditch Creek Fire of ‘74 has reached climax community.

MethodsHow did we do it?

Prepare data sheet

with placeholders for percentages of bare

ground, grasses, Forbes and Shrubs and the

height of the highest shrub

Prepare Daubenmire

FrameLength: 61 cm; Width:

37.8 cmDivide it into 30 ca.

equal quadratesNew Frame size allowed more area to be sampled

TOTAL AREA: 532m²

Taking Pictures

from Midpoint

Take pictures from average eye level in all points of the compass (real directions) with

the horizon in the upper third of the

picture

NorthWest

East South

Create Sampling MapWith 20 points in controlled and burned areas

SAMPLING

Obvious, thatthese two kids have a lot of fun!

Place Daubenmire frame on the sampling point so that the sampling

point Is in the middle of the daubenmire frame

1

Align Daubenmire frame real south2

Look from above straight down to the frame and estimate independently the percent covers of

forbes, shrubs, grasses and bare ground

3

Take the middle value of both estimates and

record it on the previously created data

sheet

4

If there was shrub (Sagebrush/bitterbrush), measure the height of

the highest shrub of connected brush

5

Weight Soil Samples in package. After drying them weight again. the

difference minus 2g (Zip-bag) is the Soil moisture content.

6

Soil moisture content

Take soil samples at marked spots by

drilling core sampler 9.6 cm in the earth and record samples in a bag

GPSRecord GPS coordinates

of perimeter and midpoints by setting

waypoints in garmin gps device

Don’t forget to journal

Record all other observations in journal

Such as Elevation, general vegetation cover and Signs of

animals

Results

Vegetation cover: Comparison between the unburned and the burned area 2009

05

10152025

3035404550

BareGround

Grasses Forbes Shrubs

Type of vegetation

Cover in %

ControlledBurned

p= 0.840

p= 0.056 p= 0.025 p= 0.007

Vegetation cover: Comparison between the burned areas in 1979

and 2009

0

10

20

30

40

50

BareGround

Grasses Forbes Shrubs

Type of vegetation

Cover in %

Burn 1979Burn 2009

p= 0.357

p= 0.343 p= 0.320 p= 0.051

Shrub cover in %

0

10

20

30

40

50

60

1970 1980 1990 2000 2010 2020

Year

Cover in %

BurnedControl

Soil moisture content in unburned and burned in 1979 and 2009

0

0.5

1

1.5

2

2.5

3

3.5

4

1979 2009

Category of sample

Moisture content in g

unburnedburn

p= 0.041 p= 0.001

Comparison of height of Sagebrush and Bitterbrush in 1979 and 2009

0

10

20

30

40

50

60

70

80

90

100

Sagebrush Bitterbrush

Type

Height in cm

BurnedControl

p= 0.025 p= 0.080

Common Name Scientific Name Notes

Sun spots Viguiera multiflora Very abundant

Big Sagebrush Artemisia tridentata very abundant

Arrowleafe Balsamroot Balsamorhiza sagittata very abundant

Buckweed family Erigonum sp. abundant

Silky lupine Lupinus sericeus abundant

Antelope brush Purshia tridentata abundant

Mountain Hollyhock Iliamna rivularis rare

Oregon grape Mahonia repens rare

Daisy Erigeron sp. rare

Common snowberry Symphoricarpos albus rare

Table 1: Species found in burned and unburned areas in the Ditch Creek burn, Grand Teton National Park 2009

Species Found

DISCUSSIONWhy is that and what does it mean?

• Climate (Precipitation)

• Soil moisture holding

• Elevation

• Idaho lies at approximately 4000-5000 feet

• Study was conducted at 6757 feet

Reasons why the Sagebrush recovery may be inhibited

Why is it important?

• Land management

• Sage brush provides more than 70% of Sage grouse diet and the nesting

• Especially in the winter important for Elk, Mule deer and Jackrabbits

• We might destroy sage habitat if we manage it based on prior knowledge (Knight 1994)

Conclusion

Short-version

• Results prove a inhibited succession of Sage brush

• Recent Sage brush succession study not applicable in local land management in Wyoming

• Our Study is able to prevent severe mistakes in local land management

Uncertainties

• We were not able to use the results of the very early studies because of major inaccuracies and therefore used the 1979 study results

• Dobenmeir method is not recommended instead we would use a line intersect method in future studies

• Some forbes couldn’t be identified because they have their flower,in another season of the year

Further research

• What is the most important cause for the inhibited succession? Go to the idaho field and sample there in a 30 years study and see what is the most important part? Climate, elevation or moisture?

Bibliography

• Kershaw, L, MacKinnon, A, & Pojar, J (1998). Plants of the Rovky Mountains. Edmonton: Lone Pine Publishing.

• Wingate, J (1990). Rocky Mountain Flower Finder. Rochester: New York.

• Knight, D (1983). Mountains and Plains : The ecology of Wyoming. Yale: Louis Stern Memorial Fund.

• Harniss, R, & Murray, R (1973). 30 Years of Vegetal Change following Burning of Sagebrush-Grass Range. Journal of Range Management, 26, 322-325.

• USDA NRCS Plant Materials Program, (2002). Big Sagebrush. Retrieved July 23, 2009, from United States Department of Agriculture Natural Ressources Conservation Service Web site: plants.usda.gov/factsheet/pdf/fs_artr2.pdf

Acknowledgements

• Thanks a lot to Dr. Dale and Mr. Mike for guidance and supervision