
Bumblebees Are Important Pollinators
Bumblebees are extremely important pollinators for agriculture both in the field and in greenhouses. Unlike honey bees, they are able to forage under cold, rainy, and cloudy conditions, so it is possible to see them in all kinds of weather. Even on an early chilly morning, you can see a bumblebee sleeping inside a flower blossom, waiting for some warmth to arrive.
The crops that bumblebees can pollinate include tomatoes,peppers, raspberries, blueberries, chives, cucumbers,apples, strawberries, alfalfa, blackberries, soybeans,sunflowers, beans, cherries, apricots, plums, almonds,nectarines, peaches, rosehips, eggplants, and cranberries.

Bumblebees are also extremely important pollinators of many flowering plants and are generalists, which means they pollinate by visiting hundreds of flowering plants.
Bumblebee Declines
There is evidence that in North America some of our bumblebee species are declining and a few are threatened with extinction. Species that seem most vulnerable are those with smaller climate tolerances, those at the edge of their climatic niches, and later emerging species. Many species in North America and around the world, are declining at a rapid rate.
Threats
Most bumblebees nest in underground nest, or old logs or crevices. You can help the bumblebees come to your property and nest by providing a ready to move in nest, just as you would to mason bees.
I have mason home plans at Home Sweet Home for Mason Bees.

Ground Nesting
Since most bumbles nest in the ground or a dry, dark cavity, you can provide a simple ground nest with a clay pot, a saucer, some straw, piece of chicken wire, and a short piece of garden hose for an entrance. The low-flying zig zag flight of a nest-site searching queen can be seen in the spring and is very distinctive.
A mature nest of a bumblebee can contain up to 400 residents, as compared to 50,000 to 80,000 honeybees, so the nest is quite small. It should be located in the shade in a dry location. The straw used preferably should be obtained from a mouse’s nest, as a queen will be attracted to the smell. For complete instructions and diagrams, go to Hartley Botanic.

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