SUPERFAMILY APOIDEA 
BEES 
It has been estimated that more than 2,500 species of bees occur 
in North America, many of which, such as the honeybee and 
bumble bee, are so common as to require no description. Fortu- 
nately, none of these insects are particularly injurious to forest 
or shade trees. On the contrary, as a group they are highly bene- 
ficial because of the prominent role so many of them play in the 
pollination of flowers. While the majority of species provision 
their nests with pollen and honey, a few lay their eggs in the cells 
of other bees where their young live as inquilines or parasites and 
feed on food stored by their hosts. Members of the superfamily 
are distinguished by the following characteristics: the pronotum 
does not extend back to the tegulae; the trochanter is single- 
jointed; the hind tarsi are dialated or thickened; and the head 
and thorax are covered with feathery hairs. 
FAMILY MEGACHILIDAE 
LEAF-CUTTING BEES 
Leaf-cutting bees are small to medium and black, blue, brown, 
gray, metallic, or purplish. Some are marked with yellow. They 
build their nests in rotten wood, in holes in solid wood, and in 
the hollow stems of plants, and they line the walls of their cavities 
with circular or oval-shaped pieces of leaves cut from various 
species of plants. A few species have been recorded damaging 
shade trees and ornamentals in various parts of the country; 
otherwise, the group is non-injurious. 
FAMILY APIDAE 
BUMBLE, CARPENTER, AND HONEY BEES 
The family Apidae is represented by more than a thousand 
species in the United States and Canada. It has been divided into 
three subfamilies—Anthrophorinae, Xylocopinae, and Apinae. 
The subfamily Anthrophorinae contains the so-called mining or 
digger bees and the cuckoo bees. A number of species collect 
pollen and nest in the ground. Certain others, such as the cuckoo 
bees, are parasitic in the nests of other bees. The adults are usu- 
ally wasp-like in appearance. Members of the subfamily Xyloco- 
pinae construct their nests in wood or plant stems and are 
commonly known as carpenter bees. The genus Xylocopa Latreille 
contains the carpenter bees. The adults look like bumble bees but 
differ in having the dorsum of the abdomen largely bare. They 
nest in solid wood. The subfamily Apinae contains the well-known 
bumble bees and honey bees. 
Considered as a whole, members of the family are far more 
beneficial than harmful. Many species are highly efficient plant 
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