Six tips for no-till
“Underground farming” might be a better name than no-till for this farming system. What goes on under the surface of the soil in your fields is more important to your success than what happens on top, with the exception of hail, floods and temperature extremes.

As an engineer who still thinks mainly about tractors and machines that run on top of the ground, I have a lot to learn about life below the surface. Living underground are thousands (actually millions) of critters including roots, worms, bacteria, fungi, mites, nematodes, protozoa, amoebae and others I can’t spell or pronounce. Amazingly, almost all of these soil organisms are beneficial, except for a few such as soybean cyst nematode, phytophthora fungus, dandelion roots, and groundhogs.  

What does tillage do to these soil-dwelling critters? I like this illustration used by Dr. Jill Clapperton, a speaker at the National No-till Conference in January. She is a prominent researcher from Lethbridge, Alberta. You are seated in a large, crowded meeting room, with 500 other farmers. Suddenly a gigantic tractor, pulling a monster chisel plow as wide as the room, roars through it. Not a very pleasant picture. But this is what soil organisms face with each tillage pass. Some are mashed, most are jostled and moved out of comfortable surroundings, and others more fortunate will be missed by tire cleats and chisel shanks.  

Her purpose was not to scare the audience, but to help farmers understand how something you do with a good reason in mind can have undesired, and often unknown, results.

Rotational tillage
Here is a riddle: If you have a 1000-acre farm, corn-soybean rotation, and you routinely no-till soybeans into corn stalks on half of it, and chisel plow the other half prior to planting corn, how many acres of no-till do you have?

The quick answer is 500. But to someone with a long term perspective, (such as a nightcrawler) the true answer is zero. Yes, for erosion control, plowing every other year is better than plowing every year. But the major improvements in soil quality only occur after 3 to 5 years of continuous no-till. At Coshocton, on the research watersheds, it took five or six years for earthworm populations to grow to the point where infiltration was significantly increased. With rotational tillage there won’t be much, if any, improvement in organic matter. Stick with no-till for long-term success.

Strip tillage
On the poorly drained soils of Ohio fall strip-till is a logical modification of no-till for corn. If you have been following our reports on strip-till you probably know we have had mixed results from OSU research and various Extension on-farm research plots. Sometimes we see a yield advantage, sometimes we don’t. The environmental advantages of strip-till, compared to plowing, make up for any slight yield deficiencies. You would need at least 5 bushel/acre more with plowing for it to equal strip-till because of extra costs.

And what about the difference in soil quality? Considering the plight of the soil organisms in the example above, strip-till only disturbs about a quarter of the soil profile. Not perfect, but look at the millions of “lives” saved.

Compared to pure no-till, strip-till warms up and drys out faster in the spring for earlier planting. Since the soil between strips is firm, it will support the tractor tires better than plowed ground, which offers more timely planting.

Controlled traffic   
If soil compaction is reducing your yields, there is no better way to minimize or eliminate the losses than controlled traffic. It is a perfect match with no-till systems, including strip-till. You don’t need a guidance system, but it can help. If you are considering a $50,000 auto steer system, adopting controlled traffic can help justify the investment.

You may find that certain fields that have not performed well in the past with no-till will give great results after subsoiling once and immediately adopting controlled traffic.

Fertilizer management and seed selection
Fertilizer management strategies that work with tillage will not be the optimum with no-till. Starter fertilizer, including N, P and K, is essential for early growth of corn. No-till soils are “nitrogen limited” because of the extra carbon, even though these soils have more total nitrogen.

Corn hybrids should be selected for cold germination rating. Use treated seed for disease control. For soybeans, use resistant varieties.

Attend the Conservation Tillage Conference
The annual Conservation Tillage and Technology Conference will be held March 3-4 at Ohio Northern University at Ada. Several of our OSU research and extension specialists will go into great depth on items I have just touched on above, and a whole lot more. Featured speakers from out of state include Ken Ferrie, George Rehm, Randy Raper, Scott Shearer and Grant Mongold. Your county Extension office and SWCD have details.

In case you are wondering, another one of those soil-dwelling critters that causes a lot of headaches in Ohio is on the agenda: slugs.

Randall Reeder, associate professor and Extension agricultural engineer, can be reached at 614-292-6648, or reeder.1@osu.edu. This column is provided by the OSU Department of Food, Agricultural and Biological Engineering.