The species chosen can be culturally, historically, or functionally significant, but it is logical to think that
species planted are generally representative of species available
from the local nursery industry at the time and may or may not
draw from the native flora of a regional ecosystem (for the purposes of this paper, the region is defined as Los Angeles County,
10,578 km
2
). Regional nursery catalogs as a data source for urban
biodiversity have not been evaluated prior to this research. Yet,
the horticultural industry has been shown to be an important contributor to regional biodiversity with regard to invasive species
distributions