Maybe tractor jockeys plant corn and don’t return until harvest, but profit-minded farmers return several times. Here’s betting you’re after top yields and profits. Check out these six reasons why it could pay to visit cornfields now.

Dave Nanda, director of genetics for Seed Genetics Direct, compiled this list and provided tips for scouting. Seed Genetics Direct sponsors Corn Watch ’21.

Related: Cool May causes delays in corn emergence

1. Pull tissue samples. Betsy Bower, agronomist with Ceres Solutions in west-central Indiana, shared tips for pulling tissue samples to monitor nutrient levels in the Corn Watch ’20 field. Ceres is providing sampling materials and covering costs of shipping and lab analysis again this year. The first sample at V5 indicated that part of the field needed sulfur. The grower made a foliar application. He left check strips on both the conventional-tilled and no-till sides of the field. Plans called for sampling areas that did and didn’t receive foliar fertilizer separately at the V12 sampling time, and again in the reproductive phase. At V12, 25 leaves are collected, pulling the top leaf with a collar. At R1 or after, 25 ear leaves are pulled to make one sample.

2. Monitor nutrient levels. Tissue sampling helps, but you can also use visual observation. Are any areas showing nitrogen or potassium deficiencies? If nitrogen deficiency is showing up, is there time for a late-season application?

3. Look for disease lesions. Which disease you see on leaves will vary depending upon weather conditions. Gray leaf spot is possible every year. Look for small, rectangular lesions. If they’re numerous and headed toward the ear leaf, consider making a fungicide application.

4. Stay alert for insects. The biggest threat until ears are pollinated is silk clipping. Japanese beetles and corn rootworm beetles are the biggest two culprits. Nanda notes that if silks are clipped within one-half inch and pollination is only 50% complete, with beetles still active, treatment may be warranted. Pull back shucks and do the shake test to assess pollination success. If silks fall away, kernels are pollinated.

You should also be on the lookout for western corn earworm, especially in northern areas, and for European corn borer. You’re more likely to see corn borer in non-GMO corn or corn without the above-ground GMO insect trait. The second brood can burrow into stalk shanks, causing injury and opening paths for disease infection.

5. Assess weed control. Pay attention to how well your herbicide program worked. If you run across patches of perennial weeds such as Canada thistle, quackgrass or johnsongrass that survived your weed control efforts, make notes for future years. If it’s a no-till field, be alert for things such as dandelions that escaped control.

6. Take final population counts. Even if you did counts when corn was small, lay off some 1/1,000 row areas, marking off 17 feet, 5 inches in 30-inch rows. Count harvestable ears. Repeat your counts at several locations at random. Nanda also advises paying attention to plants that may have emerged late and won’t contribute a full ear. If they’re not producing an ear, they’re worse than weeds because corn herbicides won’t kill those plants, he says.