Practical tips for low test-weight corn

Farmers can increase test-weight and preserve quality of grain 

By Jackie Clark

Many Ontario producers are harvesting low test-weight or damaged corn as a result of late planting and early frosts. Proper management of this grain is imperative to preserve yield and quality.

James Dyck, OMAFRA’s engineering specialist, has plenty of practical advice for farmers about harvest, drying, handling, and storage. 

Optimal harvest timing depends on “whether or not the quality is changing in the field,” Dyck told Farms.com. “The big risk this year is frost damage. Now would be a reasonable time to check late-planted corn.

 “If you have frost damage, you could see some impact on your grain, but it all depends on what stage the grain was at when the frost damage hit. If the grain was at black layer, you won’t really see a yield impact. If (the grain) was still doughy, then you could see a significant impact,” he said.

Corn “that is damaged in the field is more susceptible to diseases moving in,” he added.

Stalk breakdown and lodging are also indications that quality is deteriorating.

In these conditions, “grain will be more of a challenge to harvest because it’s more fragile,” Dyck explained. “Keep your eye on the field and, if you see things starting to go sideways with your corn crop, it’s probably a good indication to harvest.”

After harvesting, “it is possible to increase your test weight while drying,” Dyck said. “If you dry the corn more slowly, the test weight increases. You might be able to move it up a grade level.”

Cleaning grain after drying removes broken kernels and fines to improve quality for grading and ensure proper air flow in grain bins. “At the very least, when you put grain in a bin, you want to core it,” Dyck said. 

“Temperature cables hanging through the grain mass will help to identify if it’s starting to heat up,” he added. Heat is an indication of grain spoilage.

“If you don’t have that (tool), you’re going to have to look for proxy measures. The big one is smell,” he said.

Visual assessment of stored grain is tough, but farmers can watch for insect activity or mould.

“If you suspect grain is starting to go off, you want to get it out of the bin as quickly as possible to deal with it,” Dyck said.

With winter approaching “the best things farmers can do to protect themselves is aerate their grain and cool it right down,” Dyck explained. Even if insects or mould are present, growth and activity will be slow at low temperatures.