This article in today’s Oregonian is a very serious situation. Global food production is in jeopardy and all of us need to act to protect bees, and ourselves.
Pesticides in the neonicotinoid family have been identified in this situation and others as being the culprit in these die-offs. DeSantis Landscapes has historically only used one chemical in this family and has since discontinued all use of these pesticides. Pesticides in this family essentially make the plant toxic to all insects, which can be beneficial if there is trouble with insects like aphids eating the plant but because of its non-selective nature it also kills beneficial pollinators.
For an entertaining, informative and beautiful look at bees check out the movie Queen of the Sun