Nature is often seen only from an altered or artificial view. With our modern lifestyle few people take the time to study and know nature's wisdom and perfection or see its beauty and design. Instead, they regard many of the life forms, especially the insects, as having little or no meaning. They see nature as something to be dominated or manipulated. They don't see themselves as part of nature.
To understand nature, walk into the woods or meadows and look around. You'll be in the presence of many living things—plants and animals, large and small. Then look down. You'll find equal amounts of death, many expired life forms covering the soil. Dig into this mulch of dead things and you will find it beginning to decay. The deeper you dig, the more advanced the decay until the individual pieces fade into humus. This makes the soil rich and fertile to grow healthier plants. Remain for a while in the presence of this cycle of life, death, decay, and new life. Imagine yourself as part of this environment. Then study and think. A good thought to start with is, "Nature is perfectly designed, and everything, even death and insects, are designed for a purpose." Since we are the highest form of life on this earth as far as we know, consider the purpose of even the troublesome insects.
When you study from this approach, you make discoveries and learn things that would otherwise be blocked from view. The aphids, for example, are considered to be our most troublesome insect. They reproduce extremely fast. They can give birth to live young or deposit eggs. When born alive, they are all young females that are born pregnant, and their young are born pregnant. They may grow wings or not grow wings, depending on their needs. They can alter their character to suit almost any environment.
With all of these life- and generation-sustaining abilities, you think they would soon destroy all plant life, but they don't. Organic gardeners and farmers have known for years—and now science is proving—that the aphids are attracted to and can flourish best on plants that are stressed: weak and sick. The aphids act as censors to seek out and destroy the unhealthy and unfit plants. This allows "survival of the fittest," a natural law.
By destroying the unfit, the aphids have kept the plant world healthy so the plants could survive through the centuries to supply us and all other life forms with food, fiber, and energy. This censoring by the aphids makes them and the many other small insects we call troublesome very beneficial and necessary.
Except for humans, nature designed checks and balances so no single living, reproducing creature would get out of control. Nature put the lady beetles and the other predator and parasitic insects here to act as a police force to keep the aphids and other plant-censoring insects in balance and prevent them from overdoing their job.
Instead of letting nature act out its role of destroying the unfit, we put poison on the sick and weak plants to destroy the censoring insects. Then we eat from the poisoned, unfit, nutrition-poor plants and wonder why we get sick. In our failure to properly study and understand nature and our desire to dominate nature, we have caused ourselves much anguish. Poisonous synthetic chemical toxins can now be found everywhere—in most of our food and in the tissue of every human being.
We hope that reading our book about bugs will help you better understand and enjoy not only the little critters but all of nature and help you live without the need of harmful toxins. Let's help protect this beautiful and fascinating planet. It's the only home we have. Let's keep it safe and productive for ourselves and our children.
COMMON NAMES: Fall Webworm, Webworm
SCIENTIFIC NAME: Order Lepidoptera, family Arctiidae, Hyphantria cunea (fall webworm)
SIZE: Adult—1/2" to 1", larva—1" to 1 1/8"
IDENTIFICATION: These caterpillars are pale yellow or beige, black-spotted, and covered with hairs. Adults are pure satiny white to dusty brown moths. The larvae form loose, dirty white webs on terminal tree growth from spring through fall. They eat the foliage within the web.
BIOLOGY AND LIFE CYCLE: Pupae overwinter in cocoons in the soil or tree bark. Adults emerge in early summer to lay eggs in large masses on the undersides of leaves. Eggs hatch after a few days and larvae feed as a group for about four to six weeks in mid-summer. White or pale yellow cocoons form in July. Can be several generations a year.
HABITAT: Pecan, ash, willow, persimmon, hickory, apple, walnut, mulberry, and other deciduous trees.
FEEDING HABITS: Larvae eat outer foliage of trees, especially pecans. They eat fast and furiously and create an ugly mess in the foliage of trees.
ECONOMIC IMPORTANCE: The damage to trees ranges from unsightly entangled webs and partial defoliation to complete defoliation, which can badly stress trees.
NATURAL CONTROL: Protect the wasps, the birds, and the assassin bugs because they eat webworms.
ORGANIC CONTROL: Rip webs with a stick. Spray Bacillus thuringiensis or plant oil products, always at dusk, as a last resort. Use one tablespoon of molasses per gallon of spray. Catch larvae in sticky tree bands.
INSIGHT: We have noticed an increase in this pest in direct relationship to the popularity of chemical lawn care companies and the use of aerosol wasp-killer sprays. Killing the beneficials has given the webworms a free rein.
A Malcolm Story
"Why don't you have webworms, Beck?" was the question always asked by friends and visiting farmers. We had eight acres scattered with twenty big pecan trees growing around the house, in the cow lot, the chicken yard, and around various buildings. We hadn't had a single webworm colony since first purchasing the place seven years earlier. It wasn't because they were scarce. Webworms were thick, especially those years, all over the state, and I knew that I wasn't blessed with the good fortune that webworms couldn't find me or were nice enough to leave me alone.
There had to be a reason my trees were free all those years. Having a big interest in nature and reading nature books, I did read where wasps preyed on larva such as webworms and on several occasions actually saw wasps attack and carry off green loopers. I believed the wasps were doing the job, but I wasn't sure. However, I soon got proof.
Having been an abandoned farm for several years with lots of old unpainted buildings and water hole nearby, our place was a perfect environment for the wasp. All kinds of wasps had nests built everywhere. One day my two younger brothers came out when I wasn't home and spent the day knocking down wasp nests with their slingshots. The wasps never bothered me, and I never bothered them, but the temptation was too great for the boys. The nests were the perfect target, and they only missed one or two. The boys' timing must have been perfect for knocking out future wasp generations, because to this day few wasp nests have been rebuilt. The very next year we had a webworm problem.
The wasps are interesting social insects, but they are not very prolific. The males and young queens are born in late summer. Workers, males, and old queens die with the approach of winter. This leaves only the young queens, which hide in cracks, crevices, and tree bark throughout winter, emerging in the spring to start new colonies.
Other people have also found the wasp interesting and helpful. Once, when giving a talk on natural gardening to a group, I mentioned the wasp and a man in the crowd got all excited. He said, "I have a machine that will spray 100-foot-tall trees. That's what I do. I go up and down riverbottoms and spray trees for people. One day, while getting the rig ready to spray, I noticed a webworm colony in a low-hanging branch. A wasp flew in, captured a webworm, and flew off. I got interested and instead of cranking up the spray rig, I just watched. Within twenty minutes, the wasp had carried off every webworm."
About three years later, while talking to another gardening group, I told of my experience and the other man's story of the wasp. Again there was an old gentleman in the crowd who wanted to tell his story. He said, "I learned long ago the wasps were beneficial and preyed on webworms. But I noticed the wasp had a hard time getting through that web. So one day I decided to help them by taking a stick and tearing the web open. Sure enough, they would clean up a web a lot faster after I tore it. For years now I have been tearing the webs open for them. For a while it took fifteen to twenty minutes for the wasps to find the opened web; later it took them five minutes to find it. Now I can just walk out of the house with a stick and here they come."
We all laughed at this story's ending, but entomologists that study wasps claim they are the intellectuals of the insect world. They seem to have an ability to learn. The entomologist captured wasps and put them under a glass dome with a small escape hole. The wasps escaped, and each time they were caught and put back into the dome. They always looked for the opening and escaped again. No other insect they studied was able to learn or remember the escape hole.
I, too, find them pretty smart. While photographing them with a macro lens, I came within eight inches of a big nest. While I was taking time to get focused properly, they didn't bother me or fly. In fact, only one of them seemed to notice me. She watched for a while, then reached over and with a front leg tapped a neighbor on the back as if to draw his attention to me, then they both stared at me. I got the message and moved on.
As a child, I always played around pecan trees, and during the season my pockets were always full of nuts to munch on. Back then, I remember seeing an occasional webworm but never the problem of the 1950s, at least in our area. That was about the time people were learning to spray or were becoming prosperous enough to own spray equipment. I believe spraying with the wrong thing, a poison that kills too many beneficial insects, caused the webworm to eventually explode into a nuisance. I don't approve of persistent broad-spectrum insecticides, but I do believe there is a time and place for dusting and spraying. And a heavy webworm infestation is one of those times.
The adult webworm moth deposits large clusters of eggs, and without some natural check, their populations really multiply. The webworm's natural enemies aren't nearly so prolific as they once were, and years of spraying with the wrong materials have really allowed the webworm to gain a big lead. This makes us want to spray more.
Bacillus thuringiensis is a natural organism that destroys only the webworm and other lepidopterous caterpillars. It does not harm you, the wasp, the assassin bug, the praying mantis, the birds, or any of the rest of nature. Bt is being widely used in agriculture and, if properly used, works excellently on webworms.
The first time I tried it, it didn't work very well. I sprayed at about ten o'clock on a bright sunny day. I didn't realize the webworms were asleep in the web and wouldn't be feeding until dark. They must eat it before it will affect them, and by nightfall the Bt had probably degraded. So now I spray either late in the evening or on a damp cloudy day, and it is 100 percent effective.