Tom Hall, Senior Agronomist, Rooster Strategic Solutions
With three-plus decades in the field as an agronomist, I’ve seen my share of successes and failures; frankly speaking, I’ve learned more from the latter than the former! But there are common themes which continue to rise to the top, year after year. As we approach another corn harvest and begin thinking about next year, I thought I’d share some of the old school agronomy decisions that farmers should be making.
Soil testing is the foundation. The soil’s pH level can give you a quick estimate of your soil’s health and nutrient availability. If the pH is in the 6.0 to 6.9 range, key plant nutrients – calcium and magnesium – are likely sufficient. Calcium is the building block of a healthy, biologically active soil, which is the key to maximizing nutrient availability and mobility.
Take care of your soil. Below are four soil management practices that should be followed to ensure you have the healthiest environment possible for seeds:
- Ensure that pH is correct, and calcium plentiful
- Cover the field at all times with a cover crop or residue
- Practice no-till or minimum-tillage
- Never work or harvest wet fields
Together, these four factors ensure that soil is aggregated with plenty of air space; that water can move into the soil around the aggregates; that roots will flourish; and that nutrients are available to the plants. It’s the best bargain around to enhance crop growth.
Crop scouting identifies small problems before they become big problems. Proper scouting entails regular weekly or bi-weekly checks by someone trained to observe and report issues. If that means hiring a crop consultant, it’s worth the cost, as many of the threats to crops can be identified early and stopped in their tracks before the damage intensifies. Consultant scouting reports are the basis for a field by field battle plan for next year’s crop.
For instance, crop scouting can help you identify and manage likely 2021 issues such as:
- Gray Leafspot. One of the more common fungal diseases, it spreads rapidly, but can be treated early with fungicides. Choosing a hybrid with genetic resistance can significantly reduce future outbreaks.
- Soybean Sudden Death Syndrome (SDS) can be as devastating as the name implies but doesn’t have to be. SDS is a fungus present in the soil, often found in low spots in the field. It infects soybean roots before moving up the plant and killing its leaves. If plants show symptoms across the field, a combination of tolerance and seed treatment is needed.
- Corn Rootworm (CRW) can cause severe damage. Successful scouting will affect next year’s strategy. In most cases, CRW can be countered using the right CRW trait. Count how many adult beetles hatch at tasseling time; if you find more than one beetle per plant, plan on a CRW treatment. In areas of CRW resistance a combination of rotation, use of traits and controlling adult beetles may be necessary.
- Goss’s Wilt is a western corn bacterial disease that can cut yields in susceptible hybrids by as much as half. Crop rotation may solve the issue; if that’s not possible, plant a hybrid with a Goss’s rating of 1, 2, or 3 (on the Pioneer scale, the ratings are 9, 8, or 7).
- Corn Earworm (CEW) is common in the mid-south and southern corn belt. Control is easily obtained with hybrids that contain the Viptera trait (CryAb, mCry3A, Vip3A). Vip also picks up western bean cutworm and fall armyworm and prevents the feeding on ears where just three damaged kernels can mean a lost bushel.
- Scouting will identify weeds to determine the required residuals and optimum time to post spray. A common mistake is spraying weeds that are too big; to catch and spray a weed at four inches or less requires intense scouting every 3 days.
Testing new products and using field trials will help you stay ahead of weeds, diseases, and insects. On-farm testing is particularly important to evaluate hybrid susceptibility to old and new diseases. In the last fifty years farmers have seen corn fields unexpectedly melt down from northern leaf blight, gray leafspot, southern leafspot and, more recently, Goss’s Wilt and fusarium crown rot. In the last two years farmers have also been surprised by tar spot and bacterial leaf streak. For new diseases like these – as well as for some of the older ones, such as rust and fusarium – seed companies are struggling to find tolerance/resistance or testing to assign accurate ratings.
Farmers can set up their own early warning variety trials by selecting fields that are either in continuous corn or continuous soybeans. Disease pathogens survive over the winter on the previous crop’s residue, so if there are diseases on the farm, continuous corn or soybean fields are the best places to test for them.
A successful crop in 2021 starts with taking care of the soil, an inventory of pests in 2020, and evaluating past and potential new threats. For the high-tech to work, the old school agronomy must be taken care of first.