What’s Bugging You?
Not All Insects Should “Bug” You
Gardeners normally wage what seems a never-ending battle with insects, mites and other so-called pests. Big box stores and garden centers are full of insecticides, but is it wise to spray your yard indiscriminately? There are many bugs that are beneficial to nature and man.
Most of us are familiar with butterflies, moths and bees. They are the pollinators of many of our fruits and vegetables. They also provide beauty and interest to our gardens. Most people are familiar with the plight of the honey bee. Honey bee populations have been in decline across the United States due to a variety of reasons including over use of insecticides and loss of habitat. But did you know that honey bees are not native to the Americas? Yes, they were brought over on ships from Europe by the early settlers. If honey bees were not here prior to European settlement, what insects did all the pollination? Native bees and wasps did (and do) the lion’s share of pollination. We are all familiar with paper wasps – and yes they are very beneficial insects. They pollinate crops and wild plants and they also eat flies and mosquitoes. There are also many species of native bees that pollinate our crops. Some of the native bees are ground nesters. The attached photo shows a colony of ground nesting bees in the lawn of the Louisburg College library. The photo was taken the last week in March and the bees are actively foraging. At first glance the yard appears to be infested with many small ant hills, but the red clay mounds are actually exit holes for solitary bees. The bees live in underground tunnels and rear their young underground, feeding them nectar and pollen. When the bees dig the tunnels, they pile the excavated dirt on top of the ground, thus the mounds of red clay. These solitary bees are not dangerous as only one bee occupies each tunnel and they are not defensive. You can walk through this section of lawn and not be harmed, even though the bees are actively flying. The bees are only active in the spring when flowers are in bloom and will hibernate the rest of the year. If you have such a colony in your yard leave them alone for the few weeks they are active and they will disappear. But while they are active, they will pollinate your fruit trees, your garden, and many of the wild flowers we all enjoy.
One of the lesser-known benefits of many insects is that of pest control. Lady beetles, praying mantises, wasps and spiders all play a role in controlling the voracious appetites of other bugs like aphids. The larvae of lady beetles consume aphids, mealybugs and even some soft scales. Praying mantises hunt down and eat anything they can find, including each other. Small wasps lay eggs inside many caterpillars, and the young wasps destroy the caterpillars as they hatch. Spiders love to catch any type of bug they can and make a meal of it. Many people are concerned about large populations of native ants in their yards in the summer. Most native ants are completely harmless and feed on seeds and plants. Ants actually improve soil structure and aerate your yard. Even more importantly a good population of native ants will keep invasive ants like fire ants out of your yard. If you put out a soil insecticide to kill all ants in your yard you are actually opening the door for a fire ant invasion! It is best to let nature take its course and let the native ants thrive.
How can we encourage all these great garden helpers? One way is to lessen the amount of pesticides we use, and to use all pesticides carefully. Identify the insect that is causing you trouble and use as specific a pesticide as possible. Accepting a bit of damage will often give the predator insect time to do his or her work. Washing the bugs off the plants with some water will also lessen the chance of killing off predator insects.
Many plants host populations of beneficial insects among their foliage. Dill, borage, Shasta daisy, fennel and parsley are just a few of the plants that provide food and shelter for many beneficial insects. Water also helps attract beneficials to your garden. Shallow pools of cool, clear water will provide for many insects. It is also a good idea to let part of your yard go ‘wild’. Let it grow up to provide wild food and cover for the many beneficial insects that need wild flowers and a place to nest and hide from predators.
Observation and patience are your two best tools for developing populations of beneficial insects. Look for the presence of these helpful insects before you spray, and spray only as needed. Give your “beneficial neighbors” time to do their work before you do anything.
For more information about insects, contact your local Franklin County Cooperative Extension Office at 919-496-3344.
N.C. Cooperative Extension
Photo caption: Bees, not ants! Solitary bees tunnel into the ground to nest. Solitary bees are beneficial insects and are not dangerous. After a few weeks the bees will go in to hibernation and the mounds will disappear back in to the lawn. In the meantime the bees are pollinating plants and improving the soil structure of the lawn.