Wisconsin is one of the top states for commercial vegetable production. With the diversity of crops available in a vegetable rotation, the puzzle pieces of locating each crop within the farm can be difficult to fit together each year. One of the factors to consider when planning your crop year is preventing pest problems.
Consider relationships between neighboring fields and pest/production cycles
Crops from the same family or that have similar production cycles can be susceptible to the same pests. However, some crop-pest relationships are not as intuitive. For example, beans are susceptible to several pests that were originally considered issues in corn. Taking these relationships into consideration and not planting these crops next to each other in neighboring fields or rows can help prevent pest infestation by not creating continuous habitat for them to survive. It will also be easier to keep a pest problem isolated to one crop should one occur.
Use rotation to break pest cycles
Another thing to consider is year-over-year locations. If a pest is established in one location of the farm, rotating susceptible crops away from that location for a few years can help break a pest cycle. For example, corn rootworm larvae cannot survive long if they hatch in a field without corn in it. Planting continuous corn year after year on the same field can result in increasing pest pressure each year, in addition to nutrient management problems. Interestingly, corn rootworm has adapted to the typical corn-soy rotation by sometimes laying eggs in soybean fields, anticipating rotation into a corn crop the following year. Rotating through at least three crops can help break this cycle.
Colorado potato beetle provides another kind of challenge when planning crop rotations. At the conclusion of a growing season, adult beetles migrate to field margins to overwinter as adults in soil and plant debris. In the spring, they will emerge and walk up to a quarter mile in search of new potato plants to colonize. That means that if you rotate potato from one field to an immediately adjacent field, you will still get some of the same beetles re-colonizing your new potato field from the field margin between the old and new field. Expect higher beetle pressure in the spring from that direction.
Utilize UW-Madison’s Vegetable Crop Information Page
Keeping track of the many combinations of crops and pests can be difficult. That’s why the Wisconsin Vegetable Entomology Lab run by UW-Madison Extension Vegetable Entomologist Russell Groves has compiled this information on an easy-to-navigate page. Their crop information page goes through the main vegetable crops in Wisconsin and lists their major and minor pests along with links to further resources for reading about each. This is a quick way to see which pests overlap in which crops and can help you plan your rotations in the coming years.
Prevention is the first key to pest management and profitable growing. If you have further questions about vegetable pest management visit the Groves Lab’s Integrated Pest Management page or consult your local Extension Crops Educator.