Pest Interactions Team

Observation

Delaying cover crop termination in the spring maximizes the benefits that a cover crop provides to a cropping system. Growers across the country are showing increased interest in delaying termination of their cover crops to achieve these benefits, sometimes waiting until after their cash crop is planted to terminate the cover crop. The PSA partners who participate in our common experiment-2 (CE-2)  protocols will quantify and elucidate the benefits, and possible drawbacks, of cover crop termination timing on slugs, pests, disease, weeds, and cash crop performance.

Approach

A cover crop that grows later into the spring growing season can provide numerous benefits such as more robust weed suppression, reduced slug damage, and an increase in the amount of invertebrate predators of weed seeds and other pests; however there can also be drawbacks such as an increase in seedling disease, favoring specific insect pests, and possible effects on cash crop yield. The CE-2 protocol, which will be executed across 15 states and three years starting in fall 2020, will focus on these effects in corn as part of a corn-soybean rotation. The cover crop CE-2 teams will be using is cereal rye.

Data Collection

The team will collect information on:

  1. Disease Occurrence
    1. Seedling root rot
    2. Corn stalk rot at physiological maturity
  2. Weed Management
    1. Weed density and biomass
    2. Dominant weed populations
  3. Insect and Slug Prevalence 
    1. Early season damage to corn  by slugs, black cutworms, and true armyworms
    2. Early, mid and late-season invertebrate predator populations
  4. Cash Crop Performance
    1. Corn stands and early season growth or vigor
    2. Grain yields
Weed free soybean plot next to a weed infested plot.
Photo credit: Mirsky lab.