Home gardeners in the Rocky Mountains receive plenty of encouragement to use chemicals. In one recent Denver-area newspaper alone, I counted no less than ten recommendations for insecticides, fungicides, pesticides and sterilant sprays! In addition, the only suggestion our local money-hungry nursery retailers would hand us when our giant black walnut tree out front became infested with aphids was," ... spray 'em!" Little wonder my husband and I fell prey to the old "chemical spray is the only way" cliche.
In desperation, since we didn't want to lose our valuable nut tree, we finally called a chemical application company and asked them to come and rescue the black walnut. Mere toddlers in ecological thinking that we were at the time, we requested that a "soft" insecticide be used.
The tree was sprayed with Malathion, which we were assured was completely "safe" and would break down within 20 days. I now realize the spray company probably meant that Malathion was safe ... if you
Disgusted, we added the cost of a doctor and a veterinarian to the $15.00 we had paid for the spraying (for a total cost of $35.00) ... and a week later, when a violent rainstorm washed the Malathion off the tree, the aphids were back.
Our black walnut really suffered that summer and so did we. We felt sick every time we looked at the tree. Day by day its branches became droopier and more bare as the ravenous aphids sucked their way through its leaves. We didn't know what to do . . . but we were sure we wouldn't spray again.
Just as we were about to admit defeat, we heard of a live-ladybugs-by-mail business in California. Well, anyone who ever watched insects as a child knows the ladybug is a predator (aphids top their gourmet list) ... and here was a place where we could buy all we needed!
It didn't take an adding machine to help us compare costs, either. The ritualistic application of insecticides totaled a ridiculous minimum of $15.00a month per tree (not counting any subsequent expense for doctors and—maybe—funerals). A whole summer's worth of friendly, living, natural bug munchers—on the other hand—would set us back the fantastically low amount of only $3.00. Like a flash, we sent off our three bucks for a one-pint container of ladybugs. While waiting for them to arrive, we learned some interesting facts about natural-versus-chemical control of undesirable insects.
Heavily quoted government studies have revealed that contact poisons (such as DDT, Malathion or Parathion) are 100% effective insect controls. Unfortunately, the same handy government report does not mention that the much-glorified 100% includes (right along with the bad bugs) all beneficial pollen-carrying and predatory insects such as honey bees and ladybugs ... the productive bacteria in the soil . . . and, of course, earthworms.
A second (and noticeably less quoted) government study states that natural predatory controls—such as lovable little ladybugs—will be not less than 75% effective ... with none of the harmful side results so evident after the application of contact poisons.
Needless to say; we were more than ready to accept the 75% odds against our aphids.
The ladybugs, neatly contained in a small, sturdy box with a wire-mesh front, arrived in less than two weeks. That evening, we carefully released about half of them into the branches of the walnut tree. The rest we stored in the refrigerator where, according to instructions packed with our order, the tiny spotted beetles would keep nearly indefinitely.
The next morning we dashed out to see how our friendly helpers were doing. A hungry ladybug, we had been told, can eat 20 aphids a day . . . and ours were obviously hungry! One or more of the beetles was busily crunching aphids on every leaf we examined. With a magnifying glass, we could clearly see the banquet in progress for nearly a week ... until the "bad guys" were gone and the tree damage had stopped. Suddenly, we seldom saw a single aphid where—just a few days before—the black walnut's foliage had literally been crawling with them.
The ladybugs stayed around that summer and cleaned up the subsequently hatching aphids, fruitscales, leaf hoppers, mites and grubs. Our garden and orchard had never been so pest-free and—as an added bonus—the little beetles weren't washed away by rainstorms.
Now we order ladybugs every year and, according to our postman (who thinks it's highly amusing), we're no longer alone. More and more folks in our area are buying the predatory beetles too ... which means fewer local applications of poisonous sprays. There's even a possibility that we'll be able to stop ordering the ladybirds altogether in a couple of years since they seem to be returning to our area each spring after their winter's sleep.
Aphid epidemics are easy to recognize. The leaves of the trees they infest begin to look transparent as the ground underneath becomes sticky and shiny from the "honeydew" which the pests exude. (Many people blame their trees when they discover this residue on their cars . . . not realizing that the trees are being attacked.)
Now that we know how to control aphids, we watch neighbors' yards for signs of the insects' damage. As soon as we discover the plant lice at work, we release (with permission, of course) a few dozen of our refrigerated ladybugs.
We refer to this as our "free home trial" and are always amused to see skeptical expressions change to looks of surprise as the aphid damage stops. At $3.00 for a year's supply of friendly, good-natured, natural pest control ... we can afford to be generous!