The effects of the 2002 Hayman Fire on the ponderosa pine/bunch grass ecosystem Nick Kelley Blake Schnebly

Hypotheses Null: Crown replacement fires have the same effect on ponderosa/bunch grass ecosystems as low intensity fires. Alternative: Crown replacement fires alter the soil, vegetation, and canopy cover more than low intensity fires. shakti/fire.jpg

Background Ponderosa/Bunchgrass Historically fire-dependent -forest & tree structure “Encourage” low intensity fire -leaf sloughing Reduces competition Fire suppression has altered this regime –Ladder Fuels –Buildup –Parasites shakti/fire.jpg

Catastrophic Fires Causes Stand Replacement –Humans –Drought –Severe parasitism Effects Stand Replacement –Seed bank/Regenerators –Erosion –Type of vegetation/Weeds/Colonizers Effects Low Intensity Burns –Nutrient Flush –Clears forest litter –Prevents stand replacement fires images/fire-forest.jpg

Three Zones Control- has not burned recently and shows no fire “damage” Low intensity- burned ground vegetation, the canopy is alive and intact occasional torching Crown Replacement- full burn including the tops of trees and organics in the soil

Survey Criteria Soil temperature –Assumed temperature is not sun/shade dependent Soil moisture –Percentage by comparing wet/dry weight Canopy Cover –Percentage of footprint Species Richness –The total number of different ground plant species Species Area/Percent Coverage –The area a species of ground vegetation covers

Materials Compass Soil Corer Thermometer Inclinometer GPS Digital Camera Tape Measure Flags Vegetation Key 1/2 meter Grid Plastic Bags Pens

Methods Random Plot Generator and Compass –Unbiased site location 6 Plots along a 25m line –Improve survey quality 1/2 Meter Grid –Identify species and estimate coverage percent Soil Temperature Soil Sample –Core to 14cm mark Canopy Cover –Estimated and averaged Location and Elevation –GPS Slope Aspect and Angle –Compass –Inclinometer survey_equipment.jpeg

Expected Results of Alternative Hypothesis The three zones –species richness/area –Canopy coverage % –Soil moisture –Soil temperature Relationship –Moisture/temperature –Temperature/Canopy

Canopy Cover Vs. Type of Burn survey/introduction.ht

Average Soil Temperature pics/12inch-thermometer.jpg

Soil Moisture Vs. Type of Burn This is a stand replacement zone

Control Area Low IntensityStand Replacement Three Types of Burn areas Percentage of Plant Species per Burn Area

Percent Coverage per Species per Zone

Canopy Cover vs. Average Soil Temperature T-Test-.632 A correlation is shown, however, it is not statistically accurate

T-Test=.121 Soil Moisture per Temperature

Results: Conclusion Supported –Canopy Cover –Soil Moisture –Species Richness –Species Area –Soil Temperature vs. Soil Moisture –Soil Temperature vs. Canopy Cover (statistical error) Discredited –Soil Temperature –Soil Temperature vs. Canopy Cover (statistical error)

Possible Sources of Error Thermometers Elevation Time of Day Date of Survey Weather Personal Bias Nonreplicable Missing samples Small sample quantity Slope aspect Slope angle Protocol Sampling error Equipment limitations

Possible Improvements/Alterations Shorter sample window Similar weather Maintaining possession of equipment Technological improvements of protocol Increase sample size Incorporate other data

Conclusions Fire maintains the stage of succession in ponderosa/bunch grass ecosystems Significant differences between zones Stand replacement fire appears to alter the ecosystem’s condition more than historical low intensity fire Stand replacement fire lowers the soil moisture, increases soil temperature, decreases canopy cover, reduces vegetation, and possibly limits re-vegetation