I have been closely watching the news related to disappearance of honey bees. I can also add that in my own massive yard that blooms from April to September here in New England, while I do see a lot of bugs, bees are long gone. While there are many theories, but the most comprehensive study by the Department of Agriculture and Environmental Protection Agency (EPA) says that there is no single reason for the decline. Many reasons are contributing to their massive deaths and these include toxic chemicals used as pesticides, global warming, mites/viruses/bacteria, and poor nutrition. As you might already know that bees are key to pollination but many farmers destroy almost all the weeds these days with chemicals and some of the weeds are essential to survival of bees.
My Life In Bits And Pieces in Massachusetts.