Deciding When Control Is Necessary
Establish a threshold at which control measures must be taken. In most cases, a certain number of pests are tolerable. Generally, when the cost of damage exceeds that of the cost of control it is time to intervene. For example, the threshold for what is considered to be a threatening Grasshopper problem in wheat fields is 8-14 per square yard. Areas outside of active growing areas will generally have higher thresholds, but should also be monitored as new pests will move through those outside areas and be trapped before damage occurs. Contact your local county extension for more information about threshold levels in your region.
To reduce pest accumulation and growth, use Cultural Controls & Practices like improving biodiversity and proactively removing weeds that provide pest habitat. Once pest populations have exceeded the thresholds that have been set consider introducing Biological Controls before resorting to chemical control measures.