Butte Falls Blowdown

Project Description

We evaluated the effects of blowdown of varied severity, salvage logging, and subsequent fuel treatments (lop and scatter, piling, and prescribed burning) on fuel profiles, fire hazard, insect infestation, and regeneration in the Butte Falls Resource Area of the Medford District of the Bureau of Land Management in southwestern Oregon. Specific project objectives were as follows:

1. Compare fuel profiles and fire hazard before and after blowdown in previously measured plots.
2. Compare fuel profiles and fire hazard among areas with (a) different blowdown severity, (b) salvage and no salvage, and (c) different post-salvage fuel treatments.
3. Determine the effects of each blowdown severity, salvage, and fuel treatment combination on insect infestation levels and tree mortality over time.
4. Determine the effects of each blowdown severity.

In regard to fuel treatments, we hypothesized that prescribed burning will result in the highest reduction in fuels and fire hazard, while the lop and scatter treatment will result in the lowest reduction of fuels and fire hazard. We expect insect infestation will be highest in areas with heavy blowdown and no subsequent salvage and lowest in areas with salvage and fuel treatments. Finally, we expect tree regeneration in the short term (3 years post-blowdown) to be highest in areas with light blowdown (and no fuel treatment) and lowest in areas with blowdown, salvage, and fuel treatments.

Purpose and Scope

We intended to determine the effects of blowdown and subsequent logging and fuel treatments on fuel loads and fire hazard. We hypothesized that there would be substantial increases in both fine and coarse woody fuels with blowdown, and that these fuel levels increased with increasing blowdown severity. We expected that salvage logging decreased coarse woody fuels but increased fine fuel levels and fire hazard. In regards to fuel treatments, we hypothesized that prescribed burning will result in the highest reduction in fuels and fire hazard, while the lop and scatter treatment will result in the lowest reduction of fuels and fire hazard. We expected insect infestation will be highest in areas with heavy blowdown and no subsequent salvage and lowest in areas with salvage and fuel treatments. Finally, we expected tree regeneration in the short term (3 years post-blowdown) to be highest in areas with light blowdown (and no fuel treatment) and lowest in areas with blowdown, salvage, and fuel treatments.

Methods

We used previously established research plots to estimate pre-blowdown fuel loads and fire hazard. Sampling of these and other plots after blowdown, after salvage logging, and again after slash treatments allowed us to determine the effects of blowdown and subsequent logging and fuel treatments on fuel loads and fire hazard. Insect infestation, tree mortality, and regeneration will be monitored over time to determine the effects of post-blowdown management activities on forest stand recovery.

Implementation

Fieldwork began in May 2009, the initial phase of a multi-year study to evaluate change in fire hazard among the treatment options of leaving blowdown as it fell, salvage logging with lop and scatter, and salvage logging with pile-and-burn treatments.

Insect infestation, tree mortality, and regeneration will be monitored over time to determine the effects of post-blowdown management activities on forest stand recovery.