PARENT SESSION
Poster Session #40: Urban Ecology.
Thursday, August 9, 2001. Presentation from 3:30 PM to 5:00 PM. Exhibition Hall

Use of native and non-native trees in urban landscaping: Consideration of ecosystem services.

GADE, KRISTIN¹, ¹

ABSTRACT- One of the primary ways that humans affect the urban ecosystem is through decisions about landscaping, for example, whether to use native versus non-native plant species. Proponents of native plants in landscaping cite benefits for wildlife and more efficient water use, especially in arid regions, as support for their stance, while many landscapers and home owners prefer non-native species for shade and their faster rates of growth, among other reasons. I am investigating a range of characteristics of native and non-native tree species commonly found in landscaping in the Phoenix metropolitan area. I quantified characteristics of various tree species related to ecological services (habitat for urban wildlife, support for pollinators) and desirability as landscape plants (allergenicity, water use, leaf drop). Data were gathered from literature sources and from the Central Arizona-Phoenix LTER site. I defined numerical scales for each characteristic. Species survey data for co-occurring plants, birds, and pollinating insects were correlated to establish use of native and non-native tree species by various organisms. Pairwise tests revealed that native trees were less allergenic and require less water and fertilizer than non-native species, but do not provide as many size choices and provide less dense shade. Consideration of ecological functions along with human needs for urban vegetation will allow landscaping decisions to be made that may enhance ecosystem services in addition to serving traditional aesthetic and functional purposes.

KEY WORDS: urban, ecosystem, services, landscaping