The University of Nebraska-Lincoln published in 2009 two new Extension Circulars with beautiful color pictures of beneficial insects. When I printed them off from the computer my wife and I were surprised at how many of these we had been killing because we thought they were hurting our plants. To get your copy of these two Extension Circulars go to your local County Extension office and ask for EC 1578 and EC 1579 (there may be a cost), or go to In the upper left in the search box write in EC 1578 or EC 1579. When the website comes up click on “pdf”. When the article appears either download or print free of charge. These publications are in pdf format that takes “Adobe Reader” which you can download free of charge.

          In a previous article I mentioned that many gardeners are going after Aphids with the insecticide “Sevin” only to discover a couple weeks later, they are worse than ever. “Sevin” is a good insecticide and widely used but it is also very deadly to many beneficial insects such as bees, other pollinators, and the “Lady Bugs” that eat Aphids. Many garden centers have gone to “Eight” which is not as harsh on beneficial insects and can even be used on many houseplants. If Aphids are a problem for you, start out using “Insecticidal Soap” rather than a harsh chemical that kills everything. Many gardeners in the past have used a dishwashing liquid but it is not a good substitute. Dishwashing liquid has a rinsing agent so the soap will rinse off our dishes and glasses but this not good on plants as you don’t want your insecticide to easily wash off your plant. Many Insecticidal Soaps are made from oils that come from the “Neem Tree” that has insecticidal qualities which is an added benefit.

          I get very upset with the commercials I hear on TV and radio and see in the newspapers and magazines that brag about their lawn insecticide and how many insects they will kill above and below the ground. I wonder why a homeowner wants to kill all their insects? The sign of a health lawn includes having many worms in the soil. And most of these formulations do not kill grubs that can be very detrimental. I also get upset when everyone advertises their 4, 5, or 6 step lawn programs that automatically include a general insecticide to kill all the insects in your lawn. The only insecticide I put on my lawn is a “preventative” grub control containing imadicloprid (Merit). In most parts of Nebraska it is not too late to apply this product. Make sure you water it in with at least one-half inch of water or rain within 24 hours. This product will not hurt your beneficial insects.

          What are some of the most common beneficial insects? The first one that comes to mind is the “Ladybug”. Ladybugs are not only effective but are economically important. They feed on many different soft-body insects with aphids being their main food source. During larval periods the Ladybug resembles a tiny, black, six legged alligator with orange spots. As larva it will gorge on about 400 aphids. After 3 or 4 weeks it attaches to a leaf or twig and enters the pupal stage. In another week the pupal skin splits and a hungry young adult emerges to resume feeding on other insects.  As an adult it may eat another 5000 aphids. Up to 1,500 tiny yellow eggs may be deposited in clusters of 10 to 50 in just a few weeks. In good years several generations may be produced. The Ladybug’s huge appetite and reproductive capacity allows it to rapidly clean out its prey.

          Probably the next well known beneficial insect is the “Praying Mantis”. The Praying Mantis, because of its appearance and attitudes, is a fascinating insect. It is strictly carnivorous and feeds on almost any insect of a size it can overcome. Praying Mantis egg cases are harvested in their natural environment. The female deposits the eggs in the fall in a frothy secretion that hardens and protects the eggs from predators and severe winter climates.  Egg cases attach to twigs, leaves, fences, etc. and many contain 50 to 400 eggs with an average of about 200.  Upon hatching in the spring the young crawl from between tiny flaps in the case and hang from silken threads about two inches below the case. After drying out, the long-legged young disperse into the vegetation leaving little, if any evidence of their appearance.  This happens within an hour or two and it is very difficult to know hatching has occurred unless the elusive, well-camouflaged young are found.

          Not so well known are the Green Lacewing and the Brown Lacewing. “The Green Lacewing is a green, soft-bodied insect with four, clear membranous wings with green veins, long hair-like antennae, and golden eyes. They are about three-fourths of an inch long. The larva are small “alligator-like” insect with a flattened body that tapers at the tail, large mandibles, greenish gray or brownish body color and about one-eight to three-fourth of an inch long. The eggs are oval, laid singly at the end of a long silken silk, pale green when first laid and later turning gray.”

          “The Brown Lacewing adult is a soft-bodied insect with four, clear membranous wings with green veins, long hair-like antennae, and golden eyes bout three-fourths inches long.”

          “For both the Green and Brown Lacewing the adults may be generalist predators or pollen and honeydew feeders, depending on the species. The larvae are generalist predators feeding on aphids, thrips, spider mites, small caterpillars, leafhoppers, mealybugs, psyllids, whiteflies, and insect eggs.” (From “Beneficial Insects I by Robert J. Wright, Terry A. DeVries, and Jim A. Kalisch. Extension Circular 1578, University of Nebraska-Lincoln Extension, Copyright 2009)

Copyright 2013