Drought may increase stalk lodging in corn
The presence of stalk rots in corn may not always result in stalk lodging, especially if the affected crop is harvested promptly. It’s not uncommon to walk corn fields where nearly every plant is upright yet nearly every plant is also showing stalk rot symptoms. Many hybrids have excellent rind strength, which contributes to plant standability even when the internal plant tissue has rotted or started to rot. However, strong rinds will not prevent lodging if harvest is delayed and the crop is subjected to weathering, e.g. strong winds and heavy rains.
A symptom common to all stalk rots is the deterioration of the inner stalk tissues so that one or more of the inner nodes can easily be compressed when squeezing the stalk between thumb and finger. It is possible by using this "squeeze test" to assess potential lodging if harvesting is not done promptly. The "push" test is another way to predict lodging. Push the stalks at the ear level, 6 to 8 inches from the vertical. If the stalk breaks between the ear and the lowest node, stalk rot is usually present. To minimize losses from stalk lodging, avoid harvest delays. Identify fields which are at greatest risk and harvest these fields first. Fields which experienced drought stress, defoliation due to hail, foliar disease injury, etc. would be prime candidates for early harvest.