Squash, zucchini and pumpkins can be pollinated by squash and gourd bees that came north thousands of years ago along with these crops from Mexico and Central America. These ground-dwelling bees rise very early, often before daybreak, well before the flowers close at mid-morning.
Many native bees are early risers, starting earlier in the season or on cloudy days when no self-respecting honeybee ventures out, one reason they make good pollinators.
Will native bees take the place of the dwindling honeybee? "They probably will," said Robbin Thorp. "I certainly hope so.'
First they need places to live. In the manicured city or suburban garden, this can be hard to find.
Places Where Bees Can Make Homes
Thorp suggests leaving a little soil uncultivated and bare--some moist, some dry--where native bees can make homes. Retired professor Wenner has left bare dirt between the flagstones in his garden so he can watch their burrowing activities; the bare patches encourage the bees to stay in the garden.
"Most native bees like the kind of place people are always trying to get rid of," he said--bare ground, dead accumulated brush and the like.
Thorp recommends keeping plenty of flowers in bloom so they have a constant pollen source and limiting the use of pesticide sprays.
"People need to realize that every time they get rid of some pest with sprays, they also get rid of bees," he said. Bees are very susceptible to many garden sprays.
It takes much longer, several years even, for native bees to rebuild their populations. Native bees reproduce slowly, often producing young only once a year, and the adults die before the young hatch.
With some kinds of leaf-cutting and mason bees, you can try building bee homes or shells that they can then build inside. It's very simple: Take a chunk of 2x4 or 4x4 and drill holes, with the grain, four to six inches deep. Several diameters of holes work for different bees, according to Thorp. The holes can be spaced rather closely. Put the block of wood on the north side of the house or under eaves, where it is at least partly shaded. Various native bees will line the drilled holes with leaves or mud and move right in.
You can buy this kind of bee house, and even bees to go in it. Entomo-Logic (9807 N.E. 140th St., Bothell, WA 98011-5132,  820-8037) is one of several small suppliers of bee homes and native bees. The homes are pre-drilled blocks of wood that you can hang in the garden. Each has 20 holes, and the holes are lined with little cardboard tubes that can be removed for cleaning. Cost is about $20.
You can also buy the tubes for $1 each, filled with live mason bee larvae. They are shipped in fall and winter and five to seven bees come inside each tube, ready to hatch. According to co-owner Kristina Williams, mason bees are gentle, do not swarm and sting only when swatted.
Mason bees are acknowledged orchard pollinators, even doing their work when ordinary honeybees are fast asleep on cloudy days, one reason they've become popular in the apple orchards of Washington state. They also pollinate apples and stone fruits (apricots, peaches and the like) in California, even during wintry weather, which is when blossoms often open.
Better crops on fruit trees this past summer probably had something to do with the sunny spring weather that encouraged early bee activity.
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Bees You Might See
Domesticated honeybees: They seem like natives but were introduced from Europe in the 17th century; they are kept in hives by beekeepers.
Feral honeybees: Escaped from hives, they live in the wild.
Africanized bees: They look like honeybees but have mated with descendants of escaped African bees.
Native bees: These have been here all along and may be big, like a bumblebee, or small, like a sweat bee.
1.) AFRICANIZED HONEYBEE
The buzz: No more harmful than the common honeybee, their aggressiveness is legendary. They are easily infuriated, and a swarm will mass on a perceived danger, delivering hundreds of stings. They are, however, good pollinators.
The look: To the untrained eye, Africanized honeybees look exactly like their European cousins.
The sting: The same as a European's as long as you are stung only once.
DISTANCE BEES WILL CHASE
European bees: Defend a distance of 350 to 450 yards.
Africanized bees: Defend up to half a mile.
TIME BEES TAKE TO ANGER
European bees: 19 seconds
Africanized bees: 3 seconds
OTHER COMMON BEES
2.) European Honeybee
The buzz: There are several strains of this bee, all valued for their honey and wax production and most of all for their prodigious pollinating. Bees have been domesti-cated since the dawn of agriculture but also exist in the wild. A "true bee" of the Apidae family.
The look: The familiar worker bee has a fuzzy, deep gold striped abdomen.
The sting: Painful but harmless except to sensitive people.
3.) Carpenter Bee