Effects of controlled-burns on native and non-native vegetation in mid-elevation dry meadows of the Umpqua National Forest

This study investigated the effects of controlled burns on native and non-native vegetation in mid-elevation dry meadows of the Umpqua National Forest.

1. The goals of the study were to determine if fire could release native seed banks and increase vigor of native bunchgrasses and forbs, while reducing populations of invasive plants (in particular the exotic annual grasses Taeniatherum caput-medusae and Cynosurus echinatus).
2. We established plots at two meadows, and half of the plots in each meadow were treated with controlled burns by the Umpqua National Forest. We then collected 2 yrs of pre-fire and 2 yrs of post fire community data. We also collected soil depth data in 3 of the 4 years.
3. Through analyses of dynamics of cover data in control and burned plots, we found that most native plants were relatively unaffected by fire. Fire appeared to temporarily decrease cover of some introduced species, but it did not promote long term change in the composition of plant communities.
4. The fire treatment did not appear to stimulate spread of exotic annual grasses, which can be a risk when using fire as a management tool in grassland plant communities.