Margaret Lauterbach

Beneficial insects can help your garden grow

Shafer Butte above Boise still holds a few patches of snow on Tuesday, May 23. To avoid frost damage, many Treasure Valley gardeners remain attentive to possible damage in their gardens until all snow has vanished from the peak.
Shafer Butte above Boise still holds a few patches of snow on Tuesday, May 23. To avoid frost damage, many Treasure Valley gardeners remain attentive to possible damage in their gardens until all snow has vanished from the peak. doswald@idahostatesman.com

Take a good look at your insect helpers, so you know who they are and what they do. Most of us know lady beetles, of course, but their larvae are not as identifiable. Think of a dark gray, flecked with yellow or orange, “alligator” about one-quarter of an inch long. That’s the “child” of a lady beetle, and that’s the critter that’s gulping aphids and other tiny critters and insect eggs. These larvae have hatched from a yellow-orange egg that was laid in a small cluster on a leaf. Ladybug eggs do not resemble eggs laid by squash bugs, even though both are laid in clusters, for squash bug eggs are dark red.

Larvae of the green lacewing, another aphid consumer, resemble the tiny alligator-like larvae of ladybugs, but they may have some white flecks on the margins of their body instead of yellow or orange. Eggs of green lacewings are affixed to hairlike stalks about a half-inch high, usually in a group on a leaf. They are hard to see, but if you’re attentive, you will see them. Adults are those light green or brown insects with wings held upright against their body, resembling a sail.

Of course, most of us also recognize honey bees that are credited with pollinating most of the flowers that produce our food. They’re not the only pollinators, but they’re the most efficient. They are also being used to distribute disease prevention chemicals to blossoms so that blueberry or strawberry farmers don’t have to spray the entire crop. This is a process they’re calling “entomovectoring.” The proper pesticidal dust (that won’t harm bees) is placed at the entrance/exit of the hive so that the bees get some on their legs as they leave to go gather nectar from flowers. Growers in Australia find it’s more effective and economical to use these “flying doctors” than to spray entire fields, to prevent gray mold on strawberries, for instance.

Another great helper in the garden is a wasp or hornet. They snatch newly hatched larvae in the garden with which to provision their egg cells, and early in summer they gobble aphids and other damaging tiny insects. The difference between them is that hornets are usually black and white, wasps are brightly colored, usually yellow and black. Both can sting repeatedly, unlike honey bees who lose their stinger at first jab. Wasps and yellow jackets look a lot alike, although yellow jackets are larger than wasps. They’re also very aggressively seeking protein foods such as the meat in your taco at the Western Idaho Fair. Yellow jackets nest in the ground. So to get ride of them, find their hole and invert a clear glass bowl over it. They don’t have a second exit. Wasps build paper or mud nests above ground.

I’ve never been stung by the wasps patrolling my garden with me, and they can detect damaging insect babies easier than I. Unless they try to build a nest in a doorway, I leave them alone. I have been thumped on the head by a wasp, warning me there is a nest being built in the doorway I was using. If you insist on spraying them or removing their nest, do it after dark. Yellow jacket traps are available that will not nail regular wasps or hornets, but safely capture and kill yellow jackets.

Overall, beneficial creatures in the garden prey on or parasitize other creatures, some only targeting those we consider destructive, others preying on destructive and other beneficial insects alike. Preying mantises attack and consume bees as well as earwigs and other beneficial insects, for instance. Earwigs also eat aphids, so are considered beneficial by entomologists, but not by gardeners who cook.

Other beneficial insects include hover flies, which look like small bees frequently seen hovering over plants; spiders; some mites (some are destructive); rove and ground beetles, and centipedes. Millipedes, pillbugs and sowbugs (some call them roly-polys or even potato bugs) are beneficial in that they start the decay process for vegetative matter. Sowbugs or pillbugs do occasionally consume items such as strawberries that hang to the ground.

Send garden questions to melauter@earthlink.net or Gardening, The Statesman, P.O. Box 40, Boise, ID 83707.

Has frost danger passed?

It’s not really “safe” from losing frost-tender plants here until the snow on Shafer Butte has melted. In the belief that snow has at least started the melting process and is well on its way to disappearing, many of us (including me) plant earlier and lose plants to frost. We really should wait until it’s gone.

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