Comparing revegetationmethodologies for brush pile burn

sites

Scott GardnerMark Simmons

Steve Windhager

Initial Assumptions

• The process of burning brush creates a scar thatseldom recovers to pre-existing conditions.

• The heat from the burn damages the seed bankand soil microbial community, preventingrevegetation.

• This void is often filled with undesirable, and/ornon-native vegetation.

Research Questions

• Does the addition of non-sterilized soilaffect the rate of recovery?

• Does the addition of seed affect the rate ofrecovery?

Hypotheses

• The addition of local non-sterilized soil willincrease the rate of recovery

• The addition of seed will increase the rateof recovery

C.L. Browning Ranch

Site 1 – Seed Addition May 2004

Site 2 – Seed Addition May 2004

Site 5 – Seed Addition May 2004

Site 8 – Soil Addition May 2004

Site 9 – Soil Addition May 2004

Site 6 – No Treatment May 2004

2King Ranch Bluestem222Halls Panicum

111Parralenna222Prairie coneflower

111Rescue grass111Hairy Grama

111BedstrawCurly MesquiteEvolvusPersimmonGreen LillySkeleton PlantFalse Nightshade

212621262126Croton235235235cockle burr

Geranium212212212Sida33Indiangrass222little bluestem33333switchgrass566656665666green sprangletop222222221Canadian wildrye

buffalograssblue grama

444434441sideoats grama222purple three awn

big bluestemGrasses

324324324prairie verbena333333333333black-eyed Susan123123123Clasping coneflower

pink evening primrose444444443333horsemint333233323332Texas bluebonnet

212212212Texas Yellow Star555555555555standing cypress233223322332Maximillian sunflower4423Indian blanket333333333333Engleman daisy333333333333Illinois bundle flower

334334334scrambled eggs323323323plains coreopsis

American basketflower333233323332partridge pea

Flowers333333331111LITTER114111413141BARE432143214321Quad

Sept 23 - 2004July 20thMay 25-28SITE NO. 1-seed + soil

Browning Ranch Burn Pile Research Vegetation Survey

May

Cover (%

)

0

100

200

300

400F=43.5; p < 0.0001

a

b b

July

F=25.8; p < 0.001

a

b

b

September

F=24.5; p < 0.001

a

b

b

Cumulative canopy

No TreatmentSOIL

SEED

No Treatment

Cumulative Canopy

SOILSEED

No TreatmentSOIL

SEED

MAY JULY SEPTEMBER

Conclusions• The addition of unburned soil made little impact

on revegetation indicating that degradation ofthe soil may not be as significant as previouslythought.

• The data showed that successful revegetation iscontingent on seed addition, suggesting that theburn-pile process destroys much of the seedbank as well as adult plants.

• Burn-scars are therefore primarily the result oflocal "seed limitation" rather than an impairmentto the soil infrastructure or microbial community

2004 Treatment No Treatment

2007Treatment No Treatment

Site 1 – Seed Addition July 2007

SITE 3 – No Treatment2004 2007

Site 1 – Seed Addition July 2007

Site 1 – Seed Addition July 2007

Site 2 – Seed Addition July 2007

Site 5 – Seed Addition July 2007

Site 7 – No Treatment July 2007

Site 6 – No Treatment July 2007

Site 3 – No Treatment July 2007

Top 10 Speciesthat worked for us in Blanco County

1 Green sprangletop Leptochloa dubia2 Canadian wildrye Elymus canadensis3 Sideoats grama Bouteloua curtipendula4 Standing cypress Ipomopsis rubra5 Scrambled eggs Corydalis curvisiliqua6 Horsemint Monarda citriodora7 Plains coreopsis Coreopsis tinctoria8 Texas bluebonnet Lupinus texensis9 Prairie verbena Verbena bipinnatifida10 Maximillian sunflower Helianthus maximiliani

2004

Top 10 Speciesthat worked for us in Blanco County

1 Green sprangletop Leptochloa dubia2 Canadian wildrye Elymus canadensis3 Sideoats grama Bouteloua curtipendula4 Little bluestem Schizachyrium scoparium5 Yellow indiangrass Sorghastrum nutans6 Indian blanket Gaillardia pulchella7 Horsemint Monarda citriodora8 Plains coreopsis Coreopsis tinctoria9 Partridge pea Chamaecrista fasciculata10 Maximillian sunflower Helianthus maximiliani

2007

Management recommendations

• Burn during times of high soil moisture

• Locate piles in areas of high productivity

• Keep the piles under 10-feet tall

• Disc all sites after the burn

• Seed all sites two weeks after discing

• Differ grazing and mowing until little bluestem isestablished

Take-home message• Failure to reseed burn sites…

– Increases the chance for undesirable and/or non-native species to establish themselves, which oftenresults in large-scale and long-term problems

– Increases soil erosion during run-off events

– Misses the opportunity to create desirable seedislands

• So seed those burn sites!

Scott Gardner

830-868-2222