BEES: Overlooked But Essential
Most gardeners understand the link between honeybees and a bountiful harvest
of squash, peppers, melons or strawberries. So if a neighbor is a beekeeper, we
spy the tiny bees on our raspberry, apricot or cherry tree blooms. We provide the
blossoms; they ensure a bountiful harvest. Gardeners are amateur scientists,
knowledgeable that most fruiting plants are dependent upon having a bee brush
pollen onto its ovary for a fruit to form.
But honeybees are not the only excellent pollinators. Wild bees gather in our gardens hard at work but seldom noticed. This summer I
paid attention to bumblebees in my garden. Bumblebees, with their characteristic
buzz, pollinate about 15 percent of our nationís harvest as well as a wide
assortment of native flowering plants. And like the honeybee, their numbers
are dwindling. But unlike the honeybee, they donít have concerned beekeepers
trying to preserve their numbers. They have to make it on their own without much
Bumblebees are the only social
bees, aside from the honeybee. But unlike the
honeybee, they donít survive winter. Honeybees manufacture extraordinary
amounts of honey to ensure that the colony can withstand a foodless winter. In
contrast, wild bees die at the end of summer, except for the queen.
She finds a shelter, often an empty mouseís nest, and crawls inside. She
carries the requirements for a future: she has mated and will lay fertilized and
unfertilized eggs in the spring. As soon as possible, she will create waxy
chambers, lay eggs and wait for the brood to emerge. Fertilized eggs become
females; unfertilized will be males. Theyíll work through the summer only to
die within months.
No one knows the precise reason why bumblebees are disappearing. The usual
suspects may be involved: habitat loss, pesticides, parasites. Like the
honeybees wild bees are easily destroyed by pesticides or mistaken for wasps
and killed by unknowing homeowners. Here is what many donít understand: wild
bees are docile and rarely sting. They often are mistaken for wasps. Thatís
because weíre unaccustomed to look at bees closely. Many bees are solitary and
may look like flies or wasps. If you notice wild bees in your garden, rejoice.
They wonít hurt a soul and will provide the pollination a garden requires.
Bees will hover around flowers; wasps feed mostly on decaying matter or other
insects. Wasps zero in on picnic food. Bees take aim at a daisy. Wasps have
smooth, almost glassy bodies. Bees are bristly. Wasps will buzz around garbage.
Bees will buzz around crabapple blossoms. Yellowjackets, notoriously aggressive
wasps, cause most of the stings that occur throughout the summer. Some wasps,
like hornets, will build papery nests but yellowjackets usually nest
underground. And so do wild bees, which adds to the confusion.
Each year more and more wild bees make the list of endangered, valuable
insects. Gardeners have a role in protecting our most essential small creatures
by offering flowering plants from early spring to late fall. By avoiding
pesticides and encouraging native blooming plants we could contribute to the
health and well-being of wild bees. Many bees have evolved to pollinate
native plants so including natives in the garden is a plus. But even the simplest
garden variety zinnias provide nectar and pollen.
With 16 species of bumblebees in Colorado, the fuzzy body, loud hum and slow
flight announce their presence. Theyíll shake a blossom in a frenzy, a motion
called buzz pollination. This vigorous shaking releases pollen from blooms that
are have hard-to-reach places, like the elaborate folds of tomato, cranberry and
blueberry blossoms. This is why bumblebees are the preferred pollinator for most
greenhouse tomatoes. As the bees drone from bloom to bloom they build up
static electricity on their fuzzy bodies and thatís how they are able to
collect pollen on the yellow pouches that look like pantaloons.
Most wild bees fall into the wide assortment of solitary bees with thousands of
species that do not form colonies. Colorado has leafcutter bees, squash bees,
orchard mason bees, digger bees, carpenter bees and cuckoo bees, among many
others. Leafcutter bees chew a circle on the edge of a leaf. This becomes a small wrapper to lay an egg and roll
up for protection.
Squash bees, true to the name, have evolved to pollinate the squash family.
Cuckoo bees, like the cuckoo birds, lay their eggs in another beeís nest to be
raised. Left alone, wild bees come and go with little fanfare but their work in
the garden is prized.
Gardening is more than flowers or fruits. Itís the cultivation of all thatís
necessary for renewed abundance. Cultivating a healthy crop of wild bees is as
essential as growing food. The more we learn about the natural world in our
backyards, the more we can contribute to all the creatures devoted to the
survival of our beans, sunflowers, tomatoes and peppers.
For more information on wild bees: www.xerces.org is an
organization devoted to invertebrates, including wild bees.