Document Type
Article
Publication Version
Version of Record
Publication Date
10-2011
Keywords
Cheatgrass, Bromus tectorum, Exotic plant species, Intermountain West, Medusahead, Nitrate uptake, Phenotypic plasticity, Taeniatherum caput-medusae
Abstract
Differences in resource acquisition between native and exotic plants is one hypothesis to explain invasive plant success. Mechanisms include greater resource acquisition rates and greater plasticity in resource acquisition by invasive exotic species compared to non-invasive natives. We assess the support for these mechanisms by comparing nitrate acquisition and growth of invasive annual and perennial grass seedlings in western North America. Two invasive exotic grasses (Bromus tectorum and Taeniatherum caput-medusae) and three perennial native and exotic grasses (Pseudoroegneria spicata, Elymus elymoides, and Agropyron cristatum) were grown at various temperatures typical of autumn and springtime when resource are abundant and dominance is determined by rapid growth and acquisition of resources. Bromus tectorum and perennial grasses had similar rates of nitrate acquisition at low temperature, but acquisition by B. tectorum significantly exceeded perennial grasses at higher temperature. Consequently, B. tectorum had the highest acquisition plasticity, showcasing its ability to take advantage of transient warm periods in autumn and spring. Nitrate acquisition by perennial grasses was limited either by root production or rate of acquisition per unit root mass, suggesting a trade-off between nutrient acquisition and allocation of growth to structural tissues. Our results indicate the importance of plasticity in resource acquisition when temperatures are warm such as following autumn emergence by B. tectorum. Highly flexible and opportunistic nitrate acquisition appears to be a mechanism whereby invasive annual grasses exploit soil nitrogen that perennials cannot use.
Publication Title
Plant Ecology
Volume
212
Issue
10
First Page
1601
Last Page
1611
DOI of Published Version
10.1007/s11258-011-9933-z
Publisher
Springer
Rights
Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S.
Recommended Citation
Leffler, A. J.; Monaco, T. A.; and James, J. J., "Nitrogen Acquisition by Annual and Perennial Grass Seedlings: Testing the Roles of Performance and Plasticity to Explain Plant Invasion" (2011). Natural Resource Management Faculty Publications. 282.
https://openprairie.sdstate.edu/nrm_pubs/282