Strip till can be a spring routine
By JASON JOHNSON
Simultaneous strip till, fertilizer application and planting is the right springtime combination for Fayette County corn and soybean producer Collin Jensen. He saves fuel, reduces soil erosion, improves soil quality and lessens compaction by farming this way.
With this strip-till program, Jensen says, “You can cut back on equipment, machinery, fuel and man hours per acre compared to conventional farming, and at the same time lose less soil. What else are you looking for?”
Jensen, who owns and rents 1,800 acres on several farms in his northeast Iowa neighborhood, has to manage several different soil types. Some of his soils are heavier, sit on flatland and drain poorly — typical of wet spring conditions. His other soils are more characteristic of the area — better draining soils that are on steeper slopes.
Besides doing a minimal amount of subsoiling on certain fields to relieve soil compaction from manure application, Jensen leaves crop residue untouched until planting time. That’s when he uses Yetter Sharktooth trash whippers mounted on the front of his planter to prepare the soil for the seed. He has a 24-row planter, and plants rows 20 inches apart placing the seed at a 1¼- to 2-inch depth.
The trash whippers handle crop residue very well. “I’ve planted into crop residue for 25 years, and I’ve tried several types of trash whippers,” he says. “I’ve been very successful with the Yetter type I have now. I’m able to move the crop residue enough to create a clear zone in which to place the seed.”
• Most farmers strip till in the fall, fearing soils will be too wet in spring.
• You can make strip till work in spring if you wait until soils are dry enough.
• Farmer sees dramatic increase in soil organic matter with residue management.
Fertilizes while planting
In the fall, Jensen spreads dry chicken litter and performs minimal subsoiling to help lift compacted areas of soil. In spring, he applies 18 to 50 gallons (48 to 133 pounds) of 32% liquid nitrogen, running Dawn fertilizer coulters at a 4-inch depth ahead of the trash whippers while planting the corn.
Jensen performs soil sampling on each field every three to four years, by soil type, to make efficient use of costly fertilizer. “On most every farm where I grow crops, I’ve farmed that land so long now that I know where all the old field lines are,” he says. “I usually sample 5-acre areas of each field.”
Much of the land Jensen farms today was moldboard plowed before he began farming it in the 1960s. He reports dramatic increases in the amount of soil organic matter from years of practicing crop residue management.
“In my soils there is a lot of decomposed material. It looks like good stuff you would see in a compost pile,” he says. “Over time, the soil at planting depth has built up more structure and now it doesn’t crust easily.”
Economic benefits add up
Years of running a high-residue cropping system has undoubtedly saved soil for Jensen, but it has also helped improve the quality and performance of his soils.
He feels that if he can plant his crops at the same time other farmers do, he has a shot at the same yields everybody else does. “Of course, there’s give and take; no system is the best every year,” he says. Jensen cuts costs by doing his own fertilizing, planting and harvesting. Since he only makes a couple trips through his fields, he has much lower fuel costs than farmers who till conventionally. He uses about ¾ gallon per acre of fuel annually to fertilize and plant his crops.
It is important to plant on the contour in Jensen’s system because the strip-till area can be susceptible to washing after planting, since rows sit lower than the crop residue. He plants continuous corn on steeper slopes. Continuous corn helps reduce erosion, particularly during heavy rains, because of the high amount of residue.
Another issue for Jensen, as with any high-residue system, is waiting until soils are dry enough before planting. “Particularly with corn residue, I have to wait longer to get in the field than farmers who chisel plow,” he says. “To learn more about strip till and what system would work best for you, I recommend you visit your local NRCS field office.”
Johnson is with NRCS in Iowa.
Check out these tips for strip tillage
• Leave stalks standing. Collin Jensen believes it is important to leave cornstalks standing. The northeast Iowa farmer calls them the “pipeline by which water gets into the soil.” He says if the corn’s root mass is left untouched it holds more soil, and doesn’t wash into the ditches. “I like to leave stalks as tall as I can so I don’t have more matting than I want on the soil,” he explains.
• Worms are your friend. Earthworms are an important part of Jensen’s strip-till system. They help improve the quality of his soil by increasing the availability of nutrients, improving physical properties of the soil, moving crop residue deeper into the soil and enhancing the population of beneficial microorganisms. In addition, the channels in the soil created by earthworms help remove excess rainfall and snowmelt by letting more water soak in, rather than run off.
IN THE STRIP: Collin Jensen beat out some early May heavy rains by planting corn into strips in late April 2009 on this farm south of West Union.
This article published in the March, 2010 edition of WALLACES FARMER.
All rights reserved. Copyright Farm Progress Cos. 2010.