Evaluating Frost Damage To Corn
Don’t make a quick decision when assessing frost injury to corn. Above ground frost damage on small corn plants is seldom as serious as it looks. Young corn seedlings can be severely damaged above ground and still survive with little or no effect on yield. The key is to whether the growing point is below ground or above ground.
Corn younger than the five or six-leaf stage will have the growing point below ground, and therefore protected from frost injury. As long as the growing point is below ground, the corn plant is relatively safe from above-ground damage to the leaves and stem. Damage from late frosts will usually not kill corn plants younger than the 6-leaf stage.
To determine if your corn plants were destroyed by frost, the simplest advice is to wait for 3-4 days after frost injury and look for signs of regrowth. You can also determine plant viability by splitting the stem and looking at the growing point. If the plant is healthy the growing point will be firm and white or cream colored. A grey colored or soft growing point usually precedes plant death.
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