Sage advice from experience in the field
There’s no doubt about it. When it comes to continuous no-till farming, this method has humbled the best-of-the-best soil scratchers at one time or another.
For those no-till dabblers, it is important to employ all agronomic sources available. It can help to have someone with Corn Belt no-till wisdom that has been immersed in the trial-and-error learning curve from the beginning. One of those people is Dan Towery, the founder of Ag Conservation Solutions, which is based in Lafayette, Ind. This is his "dirty dozen" list of no-till misconceptions for farmers.
1 There are some soils where the practice of no-till will not work. Towery says it’s just not true. "Some soils and/or crops are easier to no-till than others, but successful no-tillers can be found everywhere." With no two fields alike, he hints to the importance of being adaptable when it comes to no-till problem-solving.
2 Soil compaction will take care of itself after three to four years with no-till. "Soil compaction might not go away by itself. Numerous freeze-thaw cycles might help, but one can’t depend on this," Towery says. "Soil compaction should be taken care of with cover crops or a ripper before beginning to no-till."
3 Planting no-till corn usually means planting later than ground that has been worked. "This might be true in the first years of no-till, but after three to five years, the soil aggregate stability improves, organic matter increases and pore size also improves," he says. This results in better soil aeration, he adds, which helps reduce soil moisture, which warms the soil.
4 Chopping cornstalks helps with decomposition, improving the seedbed for next spring. Although this will provide smaller pieces of residue, they might blow or wash away since they are not anchored. This will result in less soil being exposed to the air and might result in wetter and cooler soil at planting time.
5 Corn after corn, especially no-till corn, always takes a yield hit. "This is probably one of the biggest challenges," Towery says. "The carbon to nitrogen ratio (C:N) means that unless one has an active soil biology, there is the likelihood of nitrogen being tied up early in the growing season.
"Also, the large amount of residue might keep the soil cooler and wetter," Towery says. "A soil with more active soil biology and high earthworm populations will help break down the residue. I suggest that no-till corn after corn not be considered unless at least five years of continuous no-till or cover crops are planted for two years."
6 If no-till corn is shorter early in the growing season compared to conventional corn, then one can expect a yield reduction with no-till corn. "Cooler soil temperatures might result in slightly slower early growth, especially if the field is new to no-till.
However, as the corn grows, there is virtually no difference in height or in the resulting yield. This is less of an issue in continuous no-till fields," he says.
7 If no-till corn looks paler than conventional corn in late May or early June, then one can expect a yield decrease. Towery cautions farmers not to jump to early conclusions, particularly when something might be subjective such as color comparisons. "This is somewhat an illusion. The light colored residue background makes the green corn leaves appear to be paler as compared to bare soil."
8 Adding coulters or reside managers to a planter is the only preparation needed to no-till corn. "No—that is a big no!" Towery says emphatically. Success with no-till corn takes good management. First, the field should be free from compaction issues; have been soil tested for phosphorus, potassium and pH at maintenance levels; and have no field drainage issues.
Successful no-tillers are "adjusters" on all soil or residue contact points of the no-till planter. Various attachments might be better suited to different soil types and moisture regimes and might be added or taken off depending on the circumstances. This includes adjusting down pressure and using the proper gauge wheels, closing wheels and the usage of a seed trench firming device. He stresses the importance of the amount and placement of a starter fertilizer and planting speed to get a consistent stand. The degree of planter bounce might not be noticed in the cab, but you might end up with seeds at various planting depths.
9 Vertical tillage is no-till. "Well, maybe," Towery counters. "Vertical tillage tools that operate like a coulter cart are not too bad, but some of them have curved blades and are closer to a disk. A vertical tillage tool can size residue and mix just a little soil on it to help with the decomposition, but using it to dry the soil out and with curved blades might result in shallow surface soil compaction. Also, vertical tillage tools are oxidizing some organic matter, depending on the degree of soil and residue mixing." Towery cautions farmers to use vertical tillage only if absolutely necessary and then only to make corrections in fields with compaction or residue challenges.
10 No-till corn yields less. "For this misconception, you have to look back at what was the most limiting factor that year," he says. An improved soil [higher organic matter and greater infiltration] means there might be 5" to 7" of additional moisture available in July and August, which might result in a significant yield increase. If moisture isn’t limited, then one can expect an equivalent yield, as long as a good stand was established at planting.
11 After five years of continuous no-till, it is necessary to till to take care of hard soil and reduce nutrient stratification. "This is usually the end of the transition period, when one begins to see changes in soil properties. Some nutrient stratification occurs, but this does not affect yield. However, soil tests should be at optimal levels," Towery says. "Keep going. Tillage means starting back at square one."
12 No-till requires a higher level of management. "Not really," Towery explains. "However, there is a learning curve with anything new. There will be new issues, and one has to learn how to overcome these problems. Some farmers will find it easier to give up rather than work through the problem."