The news is full of concern over the plight of honey bees. Mites, diseases and now so-called Colony Collapse Disorder (CCD) have devastated the honeybee hives employed in agricultural pollination. With over a third of our agricultural products dependent on pollination, this will have a severe impact and could be devastating if these problems continue. Although there are many theories offered, experts do not have the answers.
Honey bees are an introduced species brought to America in the earliest stages of European colonization. But there are more than 3500 species of native bees in America and recent studies have demonstrated that a significant amount of agricultural and home garden pollination is actually provided by these natives. Unfortunately, their populations are also declining due to our urban gardening and agricultural practices. Gordon Frankie and his University of California colleagues have been studying native bees at their Berkeley demonstration gardens to determine how to best provide supportive habitat. They have identified over 50 native bee species in just the immediate Berkeley gardens. He believes we have over 80 native species in Marin. Some of these bees limit their flower forage to just one or a few native plant species, but many will be attracted to a wide variety of plants. With only a few exceptions, these native bees are solitary, not social nesters like honeybees, and need special attention to nesting and foraging habitat. As an example, most natives are ground nesters needing access to undisturbed soil. A layer of mulch may prevent a bee nesting in an otherwise satisfactory garden. Removing the mulch in a sunny, sheltered area may bring natives to the garden. A farmer could foster native bees by leaving parts of the landscape wild in native vegetation along field borders.
For more information about these fascinating and hard- working bees, check out the University research team's web site at http://nature.berkeley.edu/urbanbeegardens. There is a wealth of information, including native plant recommendations. - Glenn Smith, UCCE Master Gardeners