Spread Out Those No-Till Corn Stalk Residues!

High corn yields and no-till cropping makes spreading out crop residues critical for next spring's planting.

Published on: Oct 1, 2013

Your 2014 no-till planting season is already underway. How's that?

It begins with proper crop residue spreading, especially in no-till fields, says Sjoerd Duiker, Penn State agronomist and soils management specialist. And that's likely to pose problems if you're fortunate to be harvesting a bumper crop of corn.

"No-till crop production requires more advanced planning than tillage farming," he explains. "It's very important to evenly distribute all crop residues to guarantee excellent crop emergence next year. And," he points out, "if heavy crop residues aren't distributed uniformly behind the combine, it's very difficult to correct later."

SPREAD IT; DONT STACK IT: As combines grow wider and corn yields inch higher, importance of spreading stalk residues increases.
SPREAD IT; DON'T STACK IT: As combines grow wider and corn yields inch higher, importance of spreading stalk residues increases.

'Dumping' 9 tons in one spot?

Suppose you're combining 200-bushel corn. It's leaving almost 5 tons per acre of corn stalks and chaff in the field, calculates Duiker. That may be fine if it's spread out the width of the combine.

But if you have a 6-row combine without a spreader, most residue will end up in a 5-foot swath. That means you're stacking up nearly 9 tons of residue in that swath next to strips of bare soil. Remember, the wider the combine, the deeper you accumulate those residues.

A poorly working spreader only alleviate the problem somewhat. "If you really want to do a good job," says Duiker, "install both a residue and chaff spreader on that combine."

Some combine straw spreaders have rotating blades or batts to deflect coarse particles. But chaff may need to be spread as well with spinning disks, rotating batts or axial fans.

Chaff is lightweight, easily deflected by wind, and difficult to move very far by mechanical means. Fans are most effective. 
If your spreader has batts, it's important to replace them if they have rounded edges. Square edges on new rubber batts will increase spreader width. Adding more or longer batts or increasing the rotational speed improves residue distribution.

Straw choppers also distribute residue. Long, angled deflector blades and increased rotational speed improve their spreading action. Talk with your dealer about spreader options for your combine.

What you risk by putting it off
When the combine's running, it's tough to power it down for a fix. But here's what you risk:

* Hairpinning and variable seed depth: No-till planters with disk openers are most susceptible.

* Uneven emergence: Even if seeds are placed accurately, an excessive residue mat may cause plant injury, poor emergence or failure to emerge. Teamed with patches of bare soil, you invite uneven stands due varying soil temperatures and moisture.

* Increased pest pressure: Certain insect pests and rodents just love to live and overwinter in thick residue "hutches".

* Weed control problems: Weed seeds and grain lost through the combine will be concentrated in the residue patches and more difficult to control. Herbicide effectiveness is also compromised because the herbicides don't reach the soil.