Forbs and graminoids increased more frequently in abundance than

Forbs and graminoids increased more frequently in abundance than did shrubs across cutting, prescribed fire, and combined cutting + fire treatments (Fig. 4a–c). Shrub abundance usually decreased after treatments, a trend particularly evident after combined cutting + fire, where seven of eight (13%) studies reported that shrubs declined. Fewer studies measured species richness than measured cover, and no conclusive trends in richness emerged, except that forb richness may increase more frequently after treatment than other plant groups.

Results were mixed after wildfires: half of studies reported decreases in shrub cover while half reported increases (Fig. 4d). Frequency and magnitude of increase in non-native plant abundance (which was exclusively FK228 in vivo reported as cover) was least after cutting, intermediate BLU9931 order after prescribed fire, and greatest after cutting + prescribed fire (Fig. 5). Non-native species richness increased after all treatments, and most vigorously when cutting and prescribed fire were both applied, in all studies measuring

non-native richness. Despite these increases, non-natives comprised only small portions of total plant cover and richness. For example, non-native cover six years after prescribed fire was 1% (compared to 49% native) in mixed conifer forest in Grand Canyon National Park of Arizona (Huisinga et al., 2005), also 1% (compared to 12% native) one year after cutting + prescribed fire in the Sierra Nevada Mountains of California (Collins et al., 2007), and 10% (compared to 58% native and 4% non-native cover in the control) three years after cutting + fire in the University of Montana Lubrecht Experimental Forest (Dodson and Fiedler, 2006). Thus, native species largely constituted the total plant abundance and richness measures and corresponding responses to treatments (Fig. 2). It is noteworthy that few non-native plant data are available for wildfire Selleck Rucaparib to compare

with cutting and prescribed fire. No studies compared response to treatment between moist and dry mixed conifer forest. Effect sizes for total plant abundance after cutting (r2 = 0.04, n = 18) and prescribed fire (r2 = 0.01, n = 13) were not closely related to average long-term precipitation in study areas, indicating little relationship between response to treatment and average precipitation in this data set. Similarly, there was little relationship between effect sizes for species richness and average long-term precipitation of study areas for cutting (r2 = 0.11, n = 10) or prescribed fire (r2 = 0.00, n = 12). Results were mixed for the few studies comparing cutting intensity (Fig. 6). For prescribed fire and wildfire, high-severity burning generally (4 of 5 studies) displayed greater increase in total plant abundance and richness than did low-severity burning.

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