Cover Crop and Yield Reducing Pests – What Can You do to Reduce Potential Problems

Cover crops can provide proven benefits to your crop by increasing soil health. This includes reducing soil erosion, weed suppression, improving soil structure, moisture, drainage, storage, increasing biodiversity, and the list could go on. However, these benefits do not come without the consequences – insects. With the increase in cover cropping, we see the increase in yield reducing insects. Cover crops provide an appealing environment for these pests to lay their eggs and overwinter. From Armyworm, Black Cutworm, Seed Corn Maggots, to Grubs & Slugs, these insect and mollusk populations can put stress on your crop, unnecessary stress on you, and reduce your yields significantly.

Soybeans tend to be more vulnerable to pest infestations following a winter cover crop and your tillage practices will also make a difference. No – till and conservation tillage systems tend to create a more favorable environment for these pests compared to bare soil or conventionally tilled fields. Making sure your planter furrows are closing completely will prevent an easier access to any insects feeding on the seed and seedling growth.

There are several management strategies you can implement to keep these pests at bay. While it is a bit too late this year, make sure you are selecting cover crops from families other than what you plan on planting in the spring. For example, avoid planting soybeans into a legume cover crop.

Timely killing of the cover crop is essential to reducing insect populations that are attracted to your cover corp. Eliminating cover crops at least 2 weeks before the emergence of your crop is a good time frame to maintain to keep insect populations low. Purdue entomologists recommend avoiding planting into a green crop. If the cover crop is alive at planting, the insects in the cover crop will move to the cash crop when the cover crop finally dies. It may also be beneficial to apply an insecticide at burndown if the insect populations are expected to be large. Additionally, a timely application of insecticide post – emergence may be necessary for pests that are foliar feeders. Follow economic threshold when making these decisions to verify the profitability of the application.

Making sure you put pest scouting into your IPM and crop management program is necessary to making sure pest populations don’t get out of hand. Reducing surface residue away from emerging seedings with row cleaners or tillage to reduce potential slug and insect habitat is another strategy. And remember, the further south your crop is, the more pest risk there is. Most pests must migrate from the southern states each season.

Paying extra close attention to fields with cover crops will allow you to catch any pest issues before it’s too late for damage control. As always, give your local CaroVail a call with any concerns or for any recommendations from our team of Certified Crop Advisors.