they let bees build hives in them
Nature is helpful in many ways, trees give us oxygen to breathe, bees pollinate flowers to give us fruit, swallows stop us getting overrun by flies, its way too much to say in one wikianswer! XD
Bees are helpful to us by making honey and speading pollenation
Yes. Bees pollinate most flowers and trees. One of a bees favorite places is a orchard where fruit trees are everywhere.
BEES
we have 550 olive trees in northern CA and no bees.
It depends on what you define as helpful. Yes, all bees have a role in maintaining balance in their ecosystems, especially through pollination, but they are not neccesarily "helpful" to humans directly.
Honey bees.
Fruit trees attract bees when in bloom. Bees are also attracted to the sweetness of the fallen fruit. Apple, peach, pear, and cherry for example. Threr are always millions of honey bees that visit my plum and crabapple trees to collect pollen. (I live in North Carolina.)
Apple farmers need bees to pollinate their apple trees. Where bees have been eradicated by pesticides, more bees, or hand pollination, are necessary for the trees to bear fruit.
they spread pllen
No, honey bees typically make hives above ground in structures like trees, caves, or man-made beehives. Ground-dwelling bees like mining bees or sweat bees may create nests underground, but honey bees do not.
eat the bees (it's quite nice on toast)