Common name: Bumble Bee
Scientific name: Order Hymenoptera, family Apidae. Bumble bee--Bombus spp. Carpenter bee--Xylocopa spp.
Size: Adult--1/3" to 1"
Identification: Adults are fat, black, and fuzzy, with yellow bands on the body and spurs on the hind legs. Carpenter bees can be solid black.
Biology and life cycle: Eggs are laid in nests in cavities in the soil. They especially like abandoned field mouse nests. They have several broods per year. Larvae are fat, white grubs that stay in the nest's cells. Young queens hibernate, other forms usually die in winter. Carpenter bees or cedar bees are very similar but nest in wooden fences, patio covers, wood shingles, roof eaves, and door and window sills. They like soft cedar wood. Complete metamorphosis.
Habitat: Wood structures, soil, and in stalks of yucca and agave.
Feeding habits: Worker bees feed on the nectar of many flowering plants. Predators: Praying mantids, armadillos, and humans.
Economic importance: Pollination of ornamental and food crops; however, they are less effective than honeybees.
Natural control: Birds, wasps, and praying mantids.
Organic control: If necessary, can be controlled with soapy water or plant oil products or repelled with hot pepper products.
Insight: Bumble bees pack a powerful sting. If you don't threaten them, they usually don't sting, but they can and will if threatened. Plant pollen- and nectar-producing flowers to attract them. Praying mantids catch and eat old, slow, and not very alert bees. Bumble bees living in the ground can sometimes become very aggressive, especially when disturbed by lawn mowers or other equipment. To control, go out after dusk when the bees have gone back into the ground. Use a flashlight covered with red cellophane (bees and wasps can't see red). Pour citrus oil, or soapy water into the opening and cover it with a large rock (another tip: run away quickly). Remember that bumble bees in the garden are usually not aggressive and are highly beneficial, so hurt these friends only as a last resort. For nests under decks or outbuildings, put honey with a touch of boric acid in a small lid connected to the end of a stick.
Bumble bees nest either above or below ground depending on the species. They are opportunists, seeking out hollow areas to build their relatively small nests. Abandoned rodent burrows, unused birdhouses, old mattresses and upholstered chairs are sometimes used. The queen begins her nest in the spring by constructing hollow wax basins and places pollen in one and another for nectar. When enough pollen has accumulated, she lays one to two dozen fertilized eggs and caps the basin with more wax. The collected nectar is used by the queen as fuel during this process and eventually for workers on their outbound flights.
Then she sits on the egg chamber. Heating speeds egg hatch. After the eggs hatch the queen takes off and gathers more pollen and nectar. These young bees become the initial group of workers that create more cells, collect pollen and nectar, feed new offspring, and guard the nest while the queen continues to lay eggs. Workers perform functions as needed and may live from a couple of weeks to several months.
Bumblebee colonies in temperate climates may reach a hundred or so individuals per nest. Heading into autumn the queen lays unfertilized eggs, which develop into males, and workers supply more food to some of the larvae, that develop into queens. Reproductive bees leave the nests, mate, the males die and the newly mated queens overwinter to begin a new colony the following spring. The old queen and her offspring perish.
This review of bumblebees is certainly not intended to belittle our great friends the honeybees. It’s just that we wanted more gardeners to understand the huge value of the big bumblebees even though they don’t produce honey.