PARENT SESSION
Oral Session #29: Invasions: Predicting and understanding invasibility. Presiding: K. Kearns.
Tuesday, August 7, 2001. 1:00 PM to 4:45 PM. Madison Ballroom C.
Do species traits or habitat characteristics determine non-native plant invasion? A synthesis from Rocky Mountain National Park.
LEE, MICHELLE1,2, STOHLGREN, THOMAS1,3, 1 2 3
ABSTRACT- Some investigations have looked at species traits to assess invader success. Others have looked at habitat characteristics to assess invasion success. This study evaluated 40 non-native species and 121 0.1-ha plots in Rocky Mountain National Park to assess both species traits and habitat characteristics correlated with invasion success. Multiple regression showed that only 12% of the variance in invader success was explained by species traits, with grasses more invasive than forbs (P= 0.017). Multiple regression also showed that 60% of the variance in habitat invasion success was explained by seven habitat characteristics, mostly elevation and native species richness (P< 0.001). This study shows that (1) only a few non-native species (3 out of 40) are highly invasive in Rocky Mountain National Park; and (2) only a few habitats (13 out of 121 plots) are highly invaded in the Park. Assessing both species traits and habitat characteristics is important to evaluate the pattern of plant invasion, and may be useful for management application.
KEY WORDS: invasive plants, Rocky Mountain National Park