The attached photos show stubby root nematode injury in corn. Note the roots from the yellow corn plants are pruned, short and stubby. The normal looking plant still has stubby root injury but not as significant. This problem occurs every year when soil temperatures are cool. Counter applied at planting will greatly reduce nematode problems regardless of planting time or soil temperature. Counter however will limit post emergence herbicide products that can be used. Votivo and other nematicide materials work well when the soil temperature begins to warm and when nematode populations are low to moderate without limiting herbicide choices. Once injury is detected it will take time for new roots to regenerate before the plant can recover and pick up residual nutrition.
Problems are sometime diagnosed incorrectly in the field and the easy target to blame is fertilizer. This is why it is so important to examine the roots of every crop when grower report problems. Be prepared for growers to call regarding yellow corn this week particularly corn growing in sandy soil. I appreciate your calls and look forward to assisting you!
Harvey’s Regional Agronomist