Frozen Corn Crop? What Does That Mean?

With temperatures dipping very low in parts of the state, there may be room for concern for those with a lot of silage left on the ground. Luckily, the weather has played in our favor this harvest season, and hopefully your chopping season is well underway. Those who planned on harvesting for grain may see the benefit of chopping those fields for silage if that is an option for your farm. Any late planted fields may have very little grain fill if a  killing frost hit your crop too early.

But the question is… how much of an impact will a frost have on your crop?

You may think that frosted corn will dry down quicker than corn that didn’t get frosted, but that’s not the case. You can still expect a plant drying rate of half of a percent per day. If you have corn that hasn’t dented or reached half milk line yet – tread on the side of caution while ensiling. Both stalk and grain moisture remain high after a frost, although the appearance may fool you and trick you into thinking it’s drier than it is. If harvesting for grain, drying time and quality may be affected. An early killing freeze can reduce grain quality, as well as reduce field drying rates. As the late season temperatures get lower, an extra few days may be warranted.

There are several factors that come into play that may determine the level of damage. The following points from Pioneer explain when corn plants may be frozen.

– Corn leaf tissue can be killed by a few hours near 32F. At temperatures below 28F, leaf tissue can be frozen in a few minutes.
– Temperatures below 32F for several hours would likely kill all the leaves and some stalk material, stopping ear development.
– If only upper leaves are killed, leaves lower in the canopy will remain photosynthetically active.