Scouting is Key to Insect Pest Management in Spring

Last week, I wrote about some specific insect pests (i.e., alfalfa weevil, Timothy mite, and winter grain mite) that are becoming active in your crop fields. This list ignored some other pest species that may be active in spring forage or grain crops (e.g., cereal leaf beetle, aphids), so I wanted to take this opportunity to remind folks of the general importance of scouting.

At any one time during the growing season, various species of insects can be active in your crop fields, and individual fields will develop different communities of insects. Without occasionally walking them, it is difficult to know what insect pest species have colonized your fields and if they hold the potential to cause economic damage. Scouting your fields provides insight into what species are active, where they are active, whether pest populations are high enough to threaten crop productivity, and whether natural enemy populations have also colonized fields and may be able to provide all the control you may need.

Scouting, therefore, is vital to implementing integrated pest management (IPM) programs. Economic thresholds, which are pest populations or amounts of damage that should trigger management tactics, are based on information that should be collected by scouting. By not scouting, one runs the risk of overlooking developing pest populations or unnecessarily applying insecticides, both of which can hurt your bottom line.

At the regional scale, Penn State extension educators on the Agronomy team will provide additional insight into particular pests that we are focusing on. This regional view can provide insight into what is active in your area and what you can look for in your fields. For example, the pheromone traps we have already deployed this season are capturing some black cutworm moths. If these populations grow to be large enough to pose a risk to corn fields, we will share that information in this newsletter.  

As spring progresses in your part of Pennsylvania, I encourage you to scout your timothy, rye, barley, oats, and alfalfa for cereal rust mites (aka timothy mites), aphids, cereal leaf beetle, alfalfa weevils, and anything else you encounter. Your goal should be to have eyes on your fields every 10 days or so to determine what is active and if they pose a threat. As spring grades into summer, the active pest species will change, and corn and soybean pests will become more relevant. Frequent scouting of any crop can detect active pest populations and identify problems with weeds, pathogens, or crop nutrients. So, get out into your fields (or have someone do it for you!) to learn what is happening in your fields and properly implement integrated pest management.