Some of the most significant impacts on the global ecosystem have come from human uses of pesticides and herbicides in agriculture. These chemicals make their way into soil and water, where they cause a number of problems, from killing off unintended plants and insects to increasing the resistance of unintended targets to these very same chemicals.
What’s more, developing such chemicals is basically an ever-escalating war against pests, which breed fast enough to develop immunity to them, resulting in more and newer chemicals constantly being introduced.
In order to reduce all of this, some researchers are now suggesting that allowing weeds, in controlled numbers, to grow amidst crops might be the best option.
“The benefits of weeds have been neglected,” says Kristine M. Averill, a weed research associate at Cornell. “They’re often seen as undesirable, unwanted. We’re now beginning to quantify their benefits.”
Milkweed, for example, can be allowed to grow among corn crops because it attracts aphids, which in turn attract beneficial wasps that lay their eggs inside European corn borer eggs, which kills them. The European corn borer is one of the species that corn farmers are most worried about.
The weeds can also help in a variety of other ways such as resisting erosion and giving homes to Monarch butterflies, which the U.S. Fish and Wildlife Service is considering protecting under the Endangered Species Act because their numbers have dropped dangerously low.
As we grow ever more conscious of how human activity affects the Earth, we need to begin searching in earnest for more options like this, which allow us to preserve crop yields and other production while being better for the environment.
Nothing in nature serves only one purpose, and by studying how organisms like weeds and pest insects function in the wild, we can develop a better grasp on how they might be used in agriculture. Between this and genetic engineering, we may be able to develop agricultural systems that don’t have such an adverse effect on the world around them.