A species' successful invasion into a new site depends on its ability to persist in the local environment. An experiment was conducted to examine the response of giant reed to intermittent periods of shading for 2 yr. Results indicate that giant reed persisted when exposed to significant shading (i.e., 90% reduction of full sun) and that shading also caused changes in a number of plant characteristics, such as stem height, internode length, leaf nitrogen, leaf chlorophyll content, specific leaf area, total leaf area per plant, and leaf life span. Estimates of leaf photosynthetic rates did not differ across shade levels. Giant reed's ability to persist and grow under intermittent low-light conditions implies that plants would be poised to take advantage of sun flecks and disturbances that create gaps within the resident plant community.

Nomenclature: Giant reed, Arundo donax L. ABKDO.

Management Implications: Giant reed (Arundo donax L.) occurs throughout the southern half of the United States, from California to Maryland. It is considered an invasive plant in some parts of this range but not others. To understand how giant reed successfully invades new habitats, experiments were performed to determine the effect of shading on several aspects of its growth. Giant reed tolerated significant shading (i.e., 90% reduction of full sun) and that shading also caused changes in a number of plant characteristics, such as stem height, internode length, leaf nitrogen, leaf chlorophyll content, specific leaf weight, total leaf area per plant, and leaf life span. Giant reed's ability to persist and grow under intermittent, low-light conditions implies that the plants would be poised to take advantage of sun flecks and disturbances that create gaps within the resident plant community.