SBA of Maryland

Honey bees:

Honey bees nest in hollow trees, walls, or floors (if you can see the nest these are not likely to be honey bees)
If you see a ball of thousands of insects sitting quietly on a tree limb, fence post, or other site, this is a swarm of honey bees. A swarm is looking for a new home and will alight temporarily (hours to a few days) and then leave with no trace.
Honey bees are generally not aggressive and usually do not sting without provocation

Yellow jackets often nest in the ground
Many wasps and hornets make papery, freestanding nests attached to tree limbs or roof eaves
Mud daubers and other wasps make flatter nests with multiple cylinders attached to walls or the underside of a roof
Wasps and hornets can nest in hollow trees or other cavities
Most wasps and hornets do not sting without provocation, though yellow jackets and bald-faced hornets may sting if you are near (or step on) their nest. Multiple insects will circle you and each can sting more than once.