Corn with wind and hail damage

Editor’s note: The following was written by Sherry Hoyer for the Iowa State University Extension website published on July 15.


The crop damage in parts of Iowa from the mid-July wind and hail storms has been spotty and variable, leaving producers with everything from slight damage to complete defoliation of corn and beans. Much of the corn damage was leaning or lodging caused by high winds, with most plants having uprighted their growth by now moving into pollination.

Iowa State University Extension beef specialist Denise Schwab said fields that experienced hail damage didn’t fare as well, but may provide an opportunity for cattle producers since cattle are the ultimate upcyclers, provided fencing and water options are available.

Crop damage

“Now that we’ve had a week or two to see how the damaged crops will respond, it is time to determine the next step. If you have severely damaged fields that will not respond to make at least a partial crop, here are some recommendations for you,” Schwab said.

  • Check with crop insurance — If your crop is insured, the first call needs to be to your insurance agent to get the field adjusted and determine insurance payments.

The second question for your agent is what restrictions are in place for growing a forage crop. Are there restrictions on grazing or mechanical harvest, and are there any dates after which it can be grazed? Some will allow a cover crop to be seeded but not grazed until after Nov. 1. Also, be sure your agent has released the field before destroying the field for a new crop.

  • Check pesticide labels — If you plan to graze or harvest a forage crop, be sure to check the labels on all pesticides applied to the corn or bean crop in the last couple months.

Two key points to check include when a forage crop can be planted (crop rotation restrictions) and when can it be consumed by livestock (grazing or forage restrictions). Some herbicides may restrict germination of the forage crop, especially since we are mostly considering grass species for seeding. A handy resource to check pesticide labels for any potential restrictions is www.cdms.net/label-database.

  • Determine feed needs and how annuals can help fill them. Annual forages can fill several niches in a cattle grazing operation by stretching the grazing season and reducing the costs and stored feed needs. Summer annuals are the highest yielding and grow well in the heat of summer, provided adequate moisture is available for germination. However, by Aug. 1 it may be worth waiting until mid-August and planting cool season annuals.

Spring annual cereals, like oats or spring wheat, can provide quick growth for fall grazing and will be killed by Mother Nature, eliminating any need for herbicide to terminate the forage. Winter annual cereals, like cereal rye or winter wheat, will provide both fall/early winter grazing and early spring grazing, but they require termination in the spring prior to the 2021 grain crop. Crop insurance requirements will also impact which annuals may be most beneficial.

To determine feasible recommendations, let’s examine a few scenarios that might be options for beef producers. Provided herbicides used do not limit grass establishment, the use of summer annuals such as sorghum, sorghum X sudangrass, sudangrass or millets will provide the highest yields of forage for either grazing or mechanical harvest, as well as the widest window for grazing or harvest.

These species can be grazed prior to frost, or well into the winter, with appropriate precautions in place for prussic acid poisoning between the first frost and killing freeze. They also can be chopped for silage or wilted for baleage; however, they are not recommended for dry hay harvest due dry down difficulties.

Regardless of the species selected, all will provide optimum feed if strip grazed to reduce waste. This can be accomplished with a single electrified wire moved weekly or twice per week.

If herbicides prevent grass establishment until later in the summer, Schwab said producers might consider a mid-August seeding of spring or winter cereal grains such as oats, cereal rye, ryegrass, wheat or triticale, again with or without a legume or brassica. These are cool season crops and will grow better after the start of August rains and temperatures begin to cool.

These produce a high quality grazing forage from grain harvest until well after the killing freeze if enough growth is present. The winter-hardy cereal grains will also provide early spring grazing prior to grain planting.