Yellow jackets are numerous by mid-August. Bothersome, too, especially when we eat outdoors.

The black-and-yellow paper wasps often gather as soon as food is spread on a picnic table. They also will alight on a peach, an apple, or a cup of sweet lemonade. They may sting us if we're not careful. It's best not to swat them; better to go with conventional wisdom and play "like a tree," move slowly.

I once attended a potluck lunch at a senior center. Food dishes were spread out on two long tables positioned end to end, covering about 16 feet. Almost immediately, yellow jackets arrived. An intuitive woman brought out a portable electric fan and set the fan on one end of the long line of food. The fanned air sent the food fragrances — and the yellow jackets — away.

These small insects are social animals, and their nests are in underground holes, in burrows made by chipmunks or other animals, or at least near the ground in stumps or decaying logs. The nests are made of paper, constructed when the insects chew up wood very finely and mix it with their saliva. Try to encourage neighbors not to destroy these very active underground nests we observe in August. The wasps will not do anybody harm if we respect them, and they will patrol our yards for what we may call pests — other insects. Also, they sip sweet nectar from flowers and, so, are pollinators.

Jim Gilbert's Nature Notes are heard on WCCO Radio at 7:15 a.m. Sundays. His observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota. He taught and worked as a naturalist for 50 years.