Miner bees: Andrena sp.

The Walden Effect: Farming, simple living, permaculture, and invention.

Miner bees: Andrena sp.

Miner bee (Andrena sp.) Miner bees (also called mining or digger bees, in the genus Andrena) seem to be custom made for fruit tree pollination. The adults are present only during March and April, right when your trees are blooming, and the bees are seldom distracted by ground-flowering weeds. (Our honeybees, in contrast, seem to be spending most of their time on dead nettles at the moment.) Miner bees are also able to fly at chillier temperatures than many of the other pollinators I've discussed this week, so they're active during the morning and evening and on drippy days.

Miner bee legs are hairy I found at least two species of miner bees on our peach tree, which is to be expected since 1,300 Andrena species exist worldwide. The bees are similar in size to a honeybee --- one of my species is a bit smaller and one a bit larger --- but sparser hair on the bee's body gives the miner bee a mean look. Luckily, they're not mean at all, and are even less likely than a honeybee to sting. You can distinguish miner bees by their dark-tinted wings and extra-hairy back legs. These pollen brushes seem to go, as one website put it, "seemingly in their 'armpits'".

Despite being custom-made for fruit-tree pollination, miner bees aren't all that common in large-scale orchards. The bees won't fly very far to forage, so they require a wild nesting site close to the trees they feed from. To encourage Andrena in your garden, provide them with some loose soil near or under shrubs, preferably on a warm, south-facing bank. Your miner bees will dig a burrow in the soil and lay eggs in brood cells full of pollen and nectar, just like sweat bees do. The adults will die in late spring soon after laying their eggs, and won't be seen again until your peach trees are once again in bloom.