|Hamamelis x intermedia|
While bees are some of the most famous and loved pollinators, flies are one of the most numerous (along with beetles). I watched as a few common houseflies (Musca domestica) went from flower to flower on this potted witch hazel tree in front of a home improvement store. It has been observed of Hamamelis virginiana, an Eastern US relative of this Asian hybrid pictured above, that the primary pollinators are flies. This makes sense, because often these trees will bloom through snow, a time when bees are surely inactive due to temperature constraints. Flies are more reliable in cold seasons or harsh environments, such as alpine and tundra ecosystems, for providing pollination services to the flowering plants that inhabit such difficult environments.
|Crocus vernus 'Flower Record'|
Flies are attracted to the same things as bees, but have a much wider palette. While bees seem to have similar tastes to us, sweet or otherwise "nice" smelling plants, flies further are attracted to odors we find disgusting, like rotted flesh or other decomposing matter. The reason for this may be simple, the adults feed off the fine smelling flowers, while the foul scents are where they will look to lay eggs. Foul smelling plants that are known to be fly-pollinated are Scoliopus, Amorphophallus, and other Aroids.
The following pictures are of a shrub that I cannot identify. It is a large mounding shrub found in a local Arboretum. The smell, somewhat musky and not unlike the smell of fruit tree blossoms, is detectable from quite a distance, and that is what originally drew me in. Then, upon approaching this plant, I was amazed at the amount of flies attracted to the small inconspicuous petalless flowers. If anyone can ID this plant, or any of the flies, please share!
Update: This was recently identified as Buxus sempervirens, or possibly a similar species. It seems strange that I am so unfamiliar with a plant sold in every Home Depot and every garden center or nursery everywhere, yet able to identify native plants to the family level (at least) in my own backyard and surrounding countryside. I suppose I am a bit biased.