RACE TO THE FINISH
All photos by Tom Bechman
What can you still learn as corn enters its final phase this season? Note the nutrient-deficient leaf on the right side of the photo. Deficiencies show up later in the year.
CLASSIC FOLIAR DISEASE
Most of these lesions are likely gray leaf spot, which likes warm, humid conditions. Determine how severe lesions are — how big and how many — and how high on the plant they are. The more severe and higher up, the more likely the disease will impact yield.
WATCH FOR EAR ROTS
This ear is likely under attack because of injury from insects or some other cause that allowed water to enter the ear early. Determine if it’s just an ear here and there, or if ear rots are more widespread in the field, Dave Nanda suggests.
AERIAL VIEW HELPS
Do you have access to a licensed drone pilot? An aerial view of fields can help you size up overall health and maturity late in the season. You can’t tell if corn has reached physiological maturity without examining individual kernels. However, you can determine if parts of fields are drying down more quickly than others, and whether lodging is beginning anywhere.
DIFFERENT TYPE OF EAR MOLD
The greenish discoloration on the ear Dave Nanda is examining is likely aspergillus mold, although closer examination is needed to know for sure. It’s more commonly produced during hot, dry weather. This mold is problematic because it produces an aflatoxin, which can affect potential uses for the corn.
SIGN OF STALK ROT
Anthracnose stalk rot produces a blackish, spotty appearance on the outside of the cornstalk. Dave Nanda says it often resembles the color and consistency of shoe polish. If you begin noticing this symptom in stalks, it warrants further investigation, he says.
PROOF IS ON THE INSIDE
Here is the same stalk pictured previously split open. Notice brownish discoloration inside the pith tissue, especially around the nodes of the stalk. The rot is weakening the stalk, making it more subject to falling over if allowed to remain in the field for an extended period.