Title: | Resource use efficiency and community effects of invasive Hypochaeris radicata (Asteraceae) during primary succession |
Author(s): | Schoenfelder AC; Bishop JG; Martinson HM; Fagan WF; |
Address: | "University of Maryland, College Park, Maryland 20742 USA" |
ISSN/ISBN: | 0002-9122 (Print) 0002-9122 (Linking) |
Abstract: | "PREMISE OF THE STUDY: We sought to better understand the impacts and mechanisms underpinning a successful invasion of resource-poor sites by a nonnative plant on Mount St. Helens volcano (MSH). * METHODS: We investigated the short-term effects of the nonnative plant Hypochaeris radicata on growth of native species colonizing drought-prone primary successional surfaces under N-limited and N-augmented conditions. To understand the success of H. radicata, we compared its resource use efficiency to that of a closely related native colonist, Hieracium albiflorum, under the same conditions. * KEY RESULTS: Removing H. radicata did not affect growth of the most common colonists, but N addition demonstrated strong N limitation to growth in H. albiflorum, H. radicata, and Agrostis spp. Nonnative H. radicata exhibited lower water-use efficiency than H. albiflorum but did not differ in efficiency of N use. H. radicata biomass increased faster in response to an N pulse than did the native H. albiflorum, as did the pool of N held in H. radicata tissues. * CONCLUSIONS: Our findings contrast with results from Hawaiian volcanic sites, where higher short-term resource use efficiency was reported for invasive species, including H. radicata. Our results suggest that at MSH, the success of H. radicata relies on rapid uptake and utilization of N rather than on higher efficiency. This strategy is especially advantageous at MSH because N pulses commonly occur as a consequence of herbivore-induced mortality of Lupinus lepidus (Fabaceae)" |
Notes: | "PubMed-not-MEDLINESchoenfelder, Anna C Bishop, John G Martinson, Holly M Fagan, William F eng 2011/05/28 Am J Bot. 2010 Nov; 97(11):1772-9. doi: 10.3732/ajb.0900383. Epub 2010 Oct 1" |