Juniper Control Aspen Restoration
Aspen, Northern Great Basin
Aspen Restoration:
Selective Juniper Cutting and Prescribed Fire
Location; Steens Mountain, Oregon
Cutting Treatment – 1/3 of mature junipers cut for developing
fuels base in spring 2001.
Fall Burns – applied October 2001
Spring Burn – applied April 2002
Cooperators; Bureau of Land Management, Burns, Oregon
Otley Brothers, Inc., Diamond, Oregon
Experimental Design
5 treatment replications.
3 treatments (Control (no treatment), cut & fall burn, cut & spring
burn).
Cut &
fall burn
Cut &
spring burn
Control
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