By Grant McCarty
Local Foods and Small Farms Educator, University of Illinois Extension
For years, growers have been utilizing a process to control insects, weeds, and diseases that allows them to lessen their use of pesticide control. Known as Integrated Pest Management (IPM), this is a strategy that involves many small actions to address the overall pest problem while minimizing the use of chemical pest suppression.
The idea behind IPM is that you use strategies before your season begins, during your season, and after your season. With IPM, we hope that the strategies and process we have in place can either eliminate the need or result in less use of pesticides.
IPM follows a process which includes prevention, action, monitoring, and control. Your first step is prevention by altering the environment to keep disease and insect damage from occurring. This may be crop rotation, companion planting, floating row covers, mulches, and others. Your next step is action which requires to act or not to act.
Action is dependent on pest thresholds: number of insects and disease percent per plant. For instance, a threshold may be one adult cabbageworm per 15 cabbage plants. If you only have a couple of plants, you may not have a threshold.
Your threshold may be that action needs to occur at appearance of insect or disease. Monitoring is the next step with weekly scouting to see what the pest problem is.
Not only are you looking for adult or juvenile insects on plants but also egg sacs, damage, and insect predators like lady beetles. Then chemical control is your last step. You’ve done many actions beforehand and now are in a situation where you need to use chemical control.
Let’s look at this process further with an example of the cabbage worm. Our prevention methods may include floating row cover, black plastic/mulch, crop rotation, and companion planting.
The actions that we do are hand removal, determining our threshold, and continually monitoring. Our final step may then be spraying based on our observations and threshold.
Many of the IPM strategies for prevention are one you may already be doing such as crop rotation, mulches, companion planting, and others. IPM takes some getting used to; but once you’ve got it in place, it can really help you enjoy your gardening experience even more.