Nature Is A Moving Target

You don't know which disease, insect or weed problems will pop up next, you just know that sooner or later, problems will surface.

Published on: Feb 13, 2012

Have you ever had an older lawnmower where once you fixed one thing, something else soon popped up as a problem. Sometimes it was because you replaced the worn part, like a belt, and the new part, back to original condition, put more pressure on other, related worn parts, causing them to fail. Action led to a reaction, sometimes with unintended consequences.

Sometimes controlling pests, whether it be diseases, weeds, or insects, can be like that. Make a change in the system to try to circumvent a problem created by nature, and you're likely to encounter a different problem.

You don't have to go back too far to find examples. When farmers switched to other products besides the yellow, incorporated products in soybeans, for example, it wasn't too long before black nightshade showed up. Since it longer had competition from weeds that heads normally kept it in check, but which were now absent, it could flourish. Anyone who cleaned black nightshade purple berries pout of a combine knows that for a year or two, nature won that battle.

There are examples in corn too. Shattercane can be tough to take out because it is also a grass, and can grow at the same rate and wind up the same height of corn. If you don't eliminate the plants early, or cut off the seed heads late, it's one that spreads directly behind where the combine ran, because the seeds are relatively heavy and drop out where the combine puts them.

Most people know that after a few years of crop rotation, a variant of western corn rootworm learned how to lay eggs in soybean fields, so that crop rotation in that area no longer prevented corn rootworm problems. Now it's apparent some rootworms have mutated and adapted to handling the toxin protein in a certain genetic event.

What remains to be seen is how far that new variant of western corn rootworm will spread, and whether it will also appear in northern corn rootworm. So far, it hasn't been identified in Indiana.

What's causing this latest variant to appear? Where it's usually found, the field has been in continuous corn for years, and the farmer has used the same genetic event to attempt to con troll it year after year. Give insects too many bites of the same apple, and because they are so numerous, odds alone say that one will arrive on the scene that can handle the changed environment. Once it reproduces, the population that can handle that trait in stride begins to build.

Nature will always evolve. Your goal ought to be doing what you can to not make it as easy for them to do so.