Use conservation tillage to handle corn stalks

Tuesday, November 1, 2011

It makes for easier seedbed preparation in the spring and is the most exciting thing to happen in tillage since no-till was introduced in the late 1970s

by PAT LYNCH

If you are looking for a better way to handle corn stalks, you should have been at the demonstration at Canada's Outdoor Farm Show last September. The challenge given to the 17 companies participating was to "show producers how you would handle corn stalks."

Tillage of wheat stubble, soy ground and alfalfa is easy compared to corn stalks.

Handling corn stalks is the biggest tillage challenge. No-till has some benefits and mould board plowing has some. The newer conservation tillage tools combine the benefits of both no-till and mould board plowing to provide a better system than either.

A benefit of no-till is that it leaves trash on top, preventing erosion and holding moisture. The newer conservation tillage tools go one step further. They mix soil in the top four to six inches. This anchored residue reduces erosion better than no-till.

Mixing residue also speeds break down. More importantly, it mixes the residue so that it will hold moisture in the top six inches. This mixing helps with the destruction of disease on corn stalks. Corn stalks host fusarium, which affects wheat. If you no-till soys into corn stalks, then no-till wheat into the soys, a significant amount of corn stalks is left in the wheat crop to start fusarium in wheat. Conservation tillage reduces the amount of corn stalks left in the wheat crop.

The objective of conservation tillage is to work the corn stalks in the fall once. Leave the field so that erosion will not occur over winter. You want to be able to plant corn or beans into this field the next spring with one pass of secondary tillage. This allows you to plant two to five days earlier than if you are no-tilling. You will save one to two passes compared to chisel plowing in the fall with an older chisel plow or mould board plow.

Conservation tillage tools chop corn stalks. This cutting of corn stalks into smaller pieces allows for easier seedbed preparation in the spring. There are numerous ways to cut these stalks and this is where the tools start to separate. Some use notched disc, some use smooth discs. There are benefits to both. The size of disc varies right up to 26 inches. Some tools can be worked as shallow as one inch and some tools can go as deep as 12 inches. Some of these discs were preset at a certain angle and others at a wide range of angle settings.

The other main difference among these tools is the harrow attachment. At the show, some tools had tine harrows, others rolling baskets with different sized bars.

The folks setting up the tools were trying to guess what producers wanted to see. Most pieces of equipment had multiple options when it came to various attachments.

I listened to various producers as they walked across the field after the demonstration.

Some said there was too much dirt showing. Others said that a certain piece of equipment left too much or too little stalk showing. This is what makes tillage an art.

Different people want and need different amounts of residue left on their soil. The amount of residue depends on soil type and field slope.

The bottom line is that, if you are growing corn, you should take a look at conservation tillage with the new equipment this fall. You do not have to buy any of it. In fact, if you have 100 or 200 acres of corn, you cannot justify buying a piece. But you can rent this equipment or have someone who has bought a new tool do some acres for you.

This new conservation tillage is the most exciting thing in tillage since no-till was introduced in the late 1970s. Try it and you will like it. BF

Consulting agronomist Pat Lynch, CCA (ON), formerly worked with the Ontario agriculture ministry and with Cargill.