What’s in bloom September 2017
The hot, dry weather has caused many of the usual flowers to fade out earlier than usual, or to have lower nectar levels. In light of the dry weather, beekeepers should make sure their bees have an adequate supply of clean water nearby.
In irrigated gardens, many herbs are flowering and attracting both native and honey bees: mints, basil, sages, dill, fennel, lemon balm, bee balm, salvia, and yarrow. Many late summer garden flowers provide good forage, including sunflower, asters, echinacea, rudbeckia, borage, cosmos, anise hyssop, shasta daisies, lobelia, artichoke, Cranesbill geraniums, chrysanthemums and heptacodium. At the farm we have patches of clover and buckwheat blooming, and in weedy areas beside the fields there’s bindweed, Joe Pye weed, goldenrod, and tansy.
As for weeds, Knotweed, a member of the buckwheat family, is an excellent nectar source for a variety of pollinators, especially honey bees. Many municipalities in the Lower Mainland, however, spray or inject glyphosate (Round Up) into knotweed in order to eradicate it; bees ingest the glyphosate as it is translocated throughout the plant, including the blossoms. Although glyphosate has not been found to cause direct fatalities to honey bees, studies have shown it impacts their navigational abilities.
“…exposure to levels of GLY (glyphosate) commonly found in agricultural settings impairs the cognitive capacities needed to retrieve and integrate spatial information for a successful return to the hive. Therefore, honeybee navigation is affected by ingesting traces of the most widely used herbicide worldwide, with potential long-term negative consequences for colony foraging success.”
J Exp Biol. 2015 Sep;218(Pt 17):2799-805. doi: 10.1242/jeb.117291
Effects of sublethal doses of glyphosate on honeybee navigation. Balbuena MS,Tison L, Hahn ML, Greggers U, Menzel R, Farina WM
— Leslie Williams