Juniper Control Aspen Restoration

Aspen, Northern Great Basin

Location; Steens Mountain, Oregon

Cutting Treatment – 1/3 of mature junipers cut for developing fuels base in spring 2001.

Fall Burns – applied October 2001Spring Burn – applied April 2002

Cooperators; Bureau of Land Management, Burns, Oregon Otley Brothers, Inc., Diamond, Oregon

Aspen Restoration: Selective Juniper Cutting and Prescribed Fire

Experimental Design

5 treatment replications.

3 treatments (Control (no treatment), cut & fall burn, cut & spring burn).

ControlCut &

fall burnCut &

spring burn

Measurements:

Project has evaluated …

- Effectiveness of treatments at removing all juniper, from seedling to mature age classes.

- Aspen recruitment

- Shrub cover and density

- Understory cover, density, and diversity

Selective Cut and Fall Fire

Intense fire

September or October burns

Burned with soils dry

Higher risk of fire escape

Selective Cut and Spring Fire

Less intense fire

Late April burn

Burned with soils frozen and at field capacity

No risk of fire escape

Results

FALL BURNS

- 99.9% juniper kill

- increased aspen suckering 6 fold (10,000 ha in 2004)

- sagebrush lost, most other shrubs resprouted.

- increased bareground.

- lost most of the perennial understory except for plants with growth points below ground and with fire resistant seed.

- stimulated T&E species

Results

SPRING BURNS

- 10% of mature juniper remain.

- 50% of juniper seedlings survived. Enough to fully restock site in 70-80 years.

- Increased aspen to 5,000 ha

- Sagebrush lost only under burned trees, other shrubs resprouted or not effected.

- Understory remained largely intact. Understory cover and diversity increased 300%.

Conclusions

• Cut and Fall Burn

– most effective method for removing juniper.– greatest aspen recruitment– greater disturbance severity

• understory• hydrology

Conclusions

• Cut and Spring Burn

– less effective method for removing subcanopy and seedling juniper.

– increased aspen recruitment . . . but . . .– reduced disturbance severity

• understory• hydrology• aspen