The
focus of research in my lab is on the mechanisms and interactions that allow
some exotic plants to become invasive. Most of our current work investigates
the direct and indirect effects of the exotic invaders Typha angustifolia
L. and Phalaris arundinaceae L. on native species. We have found that
T.angustifolia has a direct allelopathic effect on the native bulrush
Bolboschoenus fluviatilis (Torrey) Sojak, which is good evidence that
T. angustifolia processes a novel weapon (Callaway and Ridenhour 2004)
that may contribute to its invasive success. We are also investigating how disturbance
(i.e., nutrient loading) affects this direct allelopathic effect. Our work with
P. arundinaceae focuses on plant-soil feedbacks. Preliminary data suggests
that P. arundinaceae has an indirect negative effect on the native Carex
stricta Lam. Results from the work on T.angustifolia and P.arundinaceae
will provide insight into how wetland communities are organized and subsequently
help mangers and conservationist control these invaders.
I
am also interested in how changes in geomorphology and hydrology affect depressional
wetland structure and function. This work has lead to the development of two
regional wetland assessment procedures for depressional and riverine wetlands
in the intermountain western US.
