Abstract Detail

Plant invasions in a time of environmental change

James, Jeremy J. [1].

Traits contributing to invasive annual grass success in low nutrient environments.

Plant invasion is classically assumed to be positively related to resource availability. However, we also know invaders can be successful in nutrient-poor systems. In practical terms this is problematic because nutrient poor systems also are difficult to restore. The research presented here centers on two questions: 1) what traits allow invasives to outperform natives on nutrient poor soils and 2) how can we use this trait information to improve our ability to restore nutrient-poor systems. Using 17 Elymus elymoides (native perennial grass) and 13 and 10 Taeniatherum caput-medusae (invasive annual grass) accessions collected from native and introduced ranges respectively, we evaluated a suite of germination, root growth, shoot growth and nitrogen use efficiency traits. Using path analysis we evaluated what trait or combinations of traits contributed most to fitness (biomass and viable seed produced) in low nitrogen soils. Early germination, root growth at low temperature and a high specific leaf area were important traits influencing variation in fitness across accessions. Nitrogen use efficiency, however, also significant variation among the accessions. There was substantial variability among accessions within a species and in some cases native plant populations had trait values similar to the invader. This means in some situation native grass accessions could be strategically paired to maximize annual grass interference in low nitrogen soils.

Broader Impacts:

1 - USDA-Agricultural Research Service, Eastern Oregon Agricultural Research Station, 67826-A Hwy 205, Burns, OR, 97720, U.S.A.

Keywords:
arid
Nitrogen
cheatgrass
medusahead.

Presentation Type: Symposium or Colloquium Presentation
Session: SY2
Location: Ballroom B/Convention Center
Date: Monday, August 2nd, 2010
Time: 8:15 AM
Number: SY2002
Abstract ID:52