Resistant Pest Populations Soar

According to a new industry study reported in the Weed’s News from invasivesspecies.org, the U.S. demand for “formulated pesticide products will approach $10 billion in 2016.” Some of the increased demand for pesticides relates to resistant pests. Resistance is both the adaptation of pests (weeds, insects, plant diseases, etc.) to a pesticide and their natural traits that block the action of a pesticide, resulting in decreased control of the pest with that pesticide. Weed resistance to glyphosate, the active ingredient in weed killer (herbicide) products such as Roundup®, Rodeo® and Kleanup® among others, is an incredibly challenging problem for agricultural producers and could potentially impact large-scale food production. As resistant weeds increase in number, the farmer or home gardener has fewer products remaining to use against resistant weeds. There are currently over 383 weeds resistant to herbicides (www.weedscience.org/summary/MOASummary.asp).

Pesticide resistance in insects and plant diseases is another developing problem. Some insects survive any insecticide application. Their genes are passed on creating a resistant population. The number of plant diseases resistant to fungicides is over 150 and there are more than 570 insects and mites resistant to insecticides (www.pesticideresistance.org). Some of the responsibility for the resistance issue is due to the overuse of chemical controls.

What can you do to avoid resistance? Use pesticides only as a last resort. This is called Integrated Pest Management (IPM). IPM uses a combination of strategies to manage pests, including insects, diseases and weeds, instead of one single method. This minimizes adverse environmental effects and reduce resistance. Chemicals should be a last resort used only to augment nonchemical pest management methods. This helps to protect the health of people, animals and the environment, prevents resurgence of problematic pests and avoids killing beneficial predator organisms that may help control pests. It also helps to reduce secondary pest outbreaks.

First, plant adapted, drought-tolerant plants that are not prone to diseases and insects. Secondly, give those plants the water, fertilizer and maintenance they require to thrive. Thirdly, monitor for pests and get them early, before they become big problems. Finally, if control is necessary, use techniques such as pruning, hosing, hoeing, trapping, mowing, hand digging and least toxic control methods such as insecticidal soap before turning to chemicals. Combine different control methods and don’t use the same chemical repeatedly. Only use pesticides when pests are at a susceptible stage and the product is likely to be effective.

Focus on prevention rather than treatment, suppression rather than eradication. Know your plants. Know your pests. Avoid letting pests get established in the first place. Call 887-2252 or email skellyj@unce.unr.edu if you have questions.