Not every column can be a dazzling trip into the breathtakingly exciting world of gardening. Occasionally the mundane intrudes, and today is one of those days.
You surely have heard of, perhaps even heard the Gen X 17 year locust, or cicadas. While the news stories do not quite quote Exodus, there is that tone about them. So what do you do if the swarms hit you? Easy answer – nothing. They do no harm to you or your plants. Spraying is neither necessary or even useful. They will soon be dead all on their own. Like teenage boys, they have only one thing on their minds. Before you grab a spray can, here is a short course on pesticides.
A pesticide is something that kills a pest. This broad classification is broken down into specific areas. Herbicides kill herbaceous material, that is, plants. Miticides kill mites, and so on. Insecticides kill, would you believe, insects, critters with six legs. But it’s not that simple. It never is.
Different insecticides work on different bugs. Or on the same bug at different stages. For example, Bt (bacillus thurengiensis) works on larva like cabbage worms but has no effect on the adults, those pretty white butterflies that flit around all summer.
More important, some formulations can be harmful for certain kinds of plants. For example Sevin, a pretty safe insecticide, should not be used on Boston ivy or Virginia creeper.
All this means that you have to pull out the reading glasses and look at the fine print on the label. It is a daunting task, but it must be done. The label will tell you everything that is important and a whole bunch of stuff that isn’t. Federal law dictates what must be there, and it is a violation of federal law to use the product in any way that is not listed on the label. In addition to a list of unpronounceable ingredients, you will find lists of all the bugs the stuff will wipe out and a list of all the plants it is safe to use it on. Read it.
You will also find a scary warning. Depending on how toxic the pesticide is, it will say, “Danger,” “Warning,” or “Caution” on the label.
The more toxic substances will give you additional instruction to wear rubber gloves (just like oven cleaner does) and goggles. Even the mildest will tell you to avoid inhaling it and keep it out of your eyes, all of which is reasonably good advice.
It only makes sense to handle pesticides with some care. But to put it in perspective, almost all over-the-counter products are safer than the cleaning supplies you keep under the sink. Some with serious sounding warnings are actually less toxic than table salt. The difference is that there is no EPA regulation regarding the labels on cleaning products or salt, and there is for pesticides.
Some pesticides are systemic, which means they become part of the plant and the insect dies whenever it eats the plant. This is the way natural pesticides, which the plant produces itself, work. Others kill by contact, which means you need to hit the bugs with the spray. Still others must be ingested. In any event, you should “spray to run-off,” that is just as the leaves begin to drip.
With many products you have a choice of buying a ready-to-use can, liquid concentrate, or dust. The ready-to-use is expensive, but it’s handy for small jobs.
Concentrate is the thing to use when you are spraying a larger area, but the leftover can’t be saved and must be disposed of properly (that’s on the label, too). The dusts have their fans, myself included, but most casual gardeners go for a liquid.
You have a wide choice. I would suggest you get a good general purpose spray now, before the word gets out and store shelves empty.