Evidence is mounting that pollinators of crop and wildland plants are declining worldwide. Our research group at UC Berkeley and UC Davis conducted a 3-year survey of bee pollinators in seven cities from Northern California to Southern California. Results indicate that many types of urban residential gardens provide floral and nesting resources for the reproduction and survival of bees, especially a diversity of native bees. Habitat gardening for bees, using targeted ornamental plants, can predictably increase bee diversity and abundance, and provide clear pollination benefits.
Frankie G, Thorp R, Hernandez J, Rizzardi M, Ertter B, Pawelek J, Witt S, Schindler M, Coville R, Wojcik V. 2009. Native bees are a rich natural resource in urban California gardens. Cal Ag 63(3):113-120. DOI: 10.3733/ca.v063n03p113