Some pesticides have been around for many, many years
Without mention of last week’s yukky names of chemical fungicides, today I am going with pesticides that have been around for hundreds, thousands of years.
Copper, sulfur, lime, tobacco; see how easy pesticide names can be?
Our way-back ancestors had to combat plant diseases and insects with things that could be found where they lived and farmed.
For instance, smoke was thought to keep away bugs and pathogens, the more aromatic the herbal smoke the better. And they might have been on to something.
Perhaps the good-smelling smoke delivered the natural pesticides since identified within some plants.
Likely the first chemical element used as a fungicide was copper and the first as an insecticide was probably sulfur.
Copper mixed with water or whatever oils available were used to combat plant fungi 2,500 years ago. And copper is still used quite a bit to this day, both by gardeners and in some commercial horticulture.
Most all the copper products at garden centers do meet the criteria for organic gardening. Sulfur at times has been used to ward off or kill off insects, fungi and nuisance critters. It is still a pesticide and repellant in use today.
Those products sold that are supposed to keep snakes away from the house? Read the ingredients; naphthalene and sulfur. Straight naphthalene is mothballs. Sulfur is also a fertilizer. Plants need sulfur in much lower amounts than the major elements like nitrogen and phosphorus, but significantly more than the “micros” such as iron and molybdenum. Plus sulfur is very acidic and thus used to keep soil that way for azaleas and blueberries.
Opposite of acidic sulfur is caustic lime. For somewhere between centuries and millenniums, lime has been important as a control agent for both plant fungi and bacteria.
Not only was it applied to food plants eons ago, but our more recent ancestors depended on lime to keep potatoes from rotting once dug and stored. In the right dose, nicotine is even worse for the health of insects than for us humans. I still see advice for making organic insecticidal tobacco tea by soaking chewing tobacco in water.
It wasn’t but a few years back we could buy E.P.A. licensed nicotine sulfate as an insecticide, complete with WARNING! and a skull and crossbones on the label.
But for a couple hundred years or so, nicotine was quite the insecticide. In addition to the tobacco and sulfur combo, there was lime-sulfur as a mixture. I think it is still used on peach tree trunks to prevent overwintering scale insects and fungi from multiplying in spring.
Copper and sulfur were long ago combined to make copper sulfate, still popular as an algaecide. About 200 years ago, vineyard owners in France came up with copper sulfate plus lime as a deterrent to human grape thieves.
Unexpected, but soon noted, the three natural chemicals compound reduced fungal leaf disease in treated vineyards.
The name Bordeaux mixture is used to this very day for the French-found fungicide composition.
Messiest stuff I’ve ever mixed and sprayed.
Terry Rector is a spokesman for the Warren County Soil and Water Conservation District.