Every so often we think it is important to remind growers about IPM, or Integrated Pest Management, and what it can do for growers. So often these days we hear about the call for applying pesticides as preventive sprays, for insurance or peace of mind, or for plant health purposes, rather than for need. There are numerous reasons why this is not the best approach to take or use of your money. First, unless you actually have the insect pest present, the insecticide application will NOT make you money! Remember, insecticides do NOT increase your yield; insecticide applications will only save the yield that an insect pest would otherwise caused to have been lost. Thus, an unnecessary insecticide application, based on the lack of an insect pest at economic population levels, will not save you any money because there was nothing present to cause an economic yield loss. It is a waste of money.
Second, and perhaps more of a long term problem, is that unnecessary applications only increase the likelihood of resistance developing to insecticides. Some of you might have heard of the term “insecticide treadmill”; this was given to situations where insecticide resistance developed on crops requiring an even greater amount and number of insecticide applications over the years. A good example is from cotton, where until recently the crop needed 12-15 insecticide applications every year to produce an acceptable yield. A major cause of this was that an IPM approach was not available nor used in the 1950s and 1960s. Insecticide resistance has been and continues to be a major concern across the country and throughout the world because it has occurred, is occurring, and will continue to be a potential occurrence. It should be mentioned that this is a concern with Bt-transgenic traits in corn, but remember, you are already attempting to prevent resistance from occurring by providing refuges whose purpose are to help prevent resistance from developing. For insecticides, the main way to prevent resistance to insecticides is to NOT use them unless absolutely necessary.
IPM has been and needs to continue to be an extremely important constituent of crop production. We have made too much progress in managing pests in an economic, effective, environmentally safe, and socially responsible manner to lose effective insecticides by not maintaining an IPM approach to pest management. In the next C.O.R.N. newsletter, we will discuss how we can use economic injury levels (EILs) and economic thresholds (ETs) in managing our insect pests in an IPM approach.
SOURCE: Ohio State University Extension