Roy Bardole was essentially sold on strip-till for corn, even before he participated in a multi-state study that compared strip-till with other tillage systems. After that study, he was more convinced than ever of strip-till's virtues.
The three-year Monsanto-sponsored trial compared fall strip-till, no-till, fall conventional tillage (disk ripper in the fall; one field cultivator pass in the spring) and spring conventional tillage (one field cultivator pass). Besides Roy and his sons, Peter and Timothy, Rippey, IA, farmers throughout the Midwest took part.
Overall, strip-till tended to have both the highest average corn yields and highest average net profit. (Profit was calculated for a three-year corn/soybean/corn rotation.)
For the Bardoles, a three-year rotation of fall strip-till corn/no-till, narrow-row soybeans/fall strip-till corn averaged 161 bu/acre in corn yield. It garnered about a $340/acre three-year profit ($113 annually).
The profit figure is based on: $2/bu corn; $5/bu soybeans; Iowa State University custom rates for field operations; and local prices for seed, fertilizer and herbicides. It does not include land costs.
The next most profitable system for the Bardoles was continuous no-till, at about $335/acre. Average no-till corn yield was 153 bu/acre.
The third most profitable system? Spring conventional tillage for corn and no-till, narrow-row soybeans, at $300/acre. Average corn yield was 155 bu/acre.
The least profitable system was fall conventional tillage for corn and conventional-till, narrow-row soybeans, at $280/acre. Average corn yield was 146 bu/acre.
“We'd been no-tilling all our corn and soybeans, but switched to strip-till corn because of the cool spring soils,” says Roy. “With strip-till, the soil is 3-4° warmer and that's all it takes to get more uniform emergence.”
Bardole reports that, in his experience, the spring soil temperatures with strip-till are equal to those with conventional tillage.
“With strip-till we have all the advantages of no-till — better water-holding in a dry year, better water absorption in a wet year, and soil-conserving residue — without any of the limitations,” Bardole notes.
Despite its obvious benefits, fall strip-till also has some snags, Bardole points out. Getting strips made in a timely manner is a primary challenge.
“We hold off on making the strips until the soil is cool enough to safely apply anhydrous ammonia, along with dry fertilizer,” he says. “But in 2000 it got very cold very early and stayed cold. As a result, we couldn't make any strips until spring and we had the usual problems associated with working ground in the spring.”
Producers who farm on the contour may have difficulty navigating a strip-till rig, says Bardole. “We need some type of guidance system for making strips and planting into them on the contour.”
At Janesville, WI, farmer-researcher-crop consultant Tim Maloney of Agri-Tech Consulting has seen both yield and net return advantages from fall strip-till.
Maloney compared conventional tillage (fall chisel followed by spring disking), no-till, fall strip-till with fall-applied anhydrous ammonia and fall strip-till with spring-applied 28% N. He spring applied 28% with herbicides to save a trip. He made his comparisons at three locations.
The fall strip-till with spring-applied N posted the highest yield at 181 bu/acre and highest net return at $108/acre. No-till came in second at a yield of 162 bu/acre and net return of $82/acre. Conventional tillage was third with 160 bu/acre and a $72/acre net return. Fall strip-till with fall-applied anhydrous finished last due to unusual weather conditions. It yielded 153 bu/acre and a $62/acre net return.
Maloney based net return on $2/bu corn, less all fixed and variable costs. He did not include government payments.
Chris Von Holten, Walnut, IL, says, “We have shifted about half our corn ground to fall strip-till. It normally gets corn off to a faster start than no-till, although the past two springs have been warm enough that there hasn't been a lot of difference between the two.”
In a 2001 comparison, Von Holten's fall strip-till corn (same hybrid) outyielded no-till corn by 5 bu/acre.
Von Holten also is comparing anhydrous ammonia injection at the time he makes the strips versus anhydrous applied in spring. His experience with fall-applied N, using N-Serve, has been satisfactory.
In 2001 testing, strip-till corn that received anhydrous in the fall of 2000 yielded 4 bu/acre more than corn (same hybrid) that received anhydrous in the spring.
For soil conservation purposes, Von Holten is staying with no-till on his hillier fields and lighter, sandier soils.