January 7, 2009

Randy Pryor, Extension Educator 

The most recent Conservation Technology Information Center (CTIC) national survey (2004) indicates no-till planting systems were used on more than 62 million acres in the United States, surpassing all other forms of conservation tillage. No-till acres continue to increase steadily and now represent 22 percent of the planted cropland compared to 6 percent in 1990.

No-till farming, especially in dryland cropping system environments, has become more popular with Nebraska farmers this past decade. In Nebraska in 1992 no-till use was reported on 1.58 million acres or 10.3 percent of the cropland. In 2004, no-till planted acres were over double that at 26.9 percent or 4.3 million acres. Nebraska leads the nation in no-till corn with over 2.4 million acres. The 2006 survey showed an increase of nearly 1 million acres of no-till in the 43 Nebraska counties surveyed totaling about 45 percent of the cropland in those counties.

Advantages of No-till

Advantages to no-till farming include time, labor and fuel savings, reduced wear and tear on machinery, better plant stands due to improving soil tilth (less soil crusting), reduced soil erosion, reduced soil water evaporation, increased water infiltration into the soil and increased soil organic matter levels over time. There are other environmental benefits to no-till farming, but the main reasons why many farmers are no-tilling dryland crops is because of the potential for higher yields in low rainfall years, timeliness in planting and being able to expand farming operations. 

Furthermore, crop insurance rates and farm program payments are tied to commodity production in the 2002 Farm Bill. According to the Nebraska Farm Business Association, the top profit center for farmers to concentrate on is crop yields per acre or bushels produced per full time person.

No-till Trial, UNL Rogers Memorial Farm

There is an ongoing long-term tillage system study on the University of Nebraska Rogers Memorial Farm (8 miles east of Lincoln). It uses a corn/soybean rotation (was sorghum/soybean) and compares no-till yields to those from different tillage practice. These research plots have shown that long-term, continuous no-till has better soil structure, more residue cover and less surface crusting than conventional tillage. The long-term no-till plots have improved water infiltration rates and reduced runoff, making rainfall more effective. With no tillage operations, better soil structure, and higher yields, UNL researcher Paul Jasa says no-till is the most profitable tillage system. The yield results from 1986 to 2004 for sorghum/soybeans and from 2005 to 2008 for corn/soybeans are in Table 1.

Compared to double disking, long-term no-till sorghum yields have averaged 12.9 bu/ac more yield and no-till soybeans have averaged 3.8 bu/ac more yield. Post cultivation was beneficial to soybean yields in earlier years when weed control was more of an issue. Now post cultivation tends to reduce yields in most years for corn, soybeans and sorghum.

Jasa compared the tillage systems with return to land and management in an economic study from 1983 through 2000 (Table 2). Taxes and land rent are not included. Custom rates, seed cost and herbicides costs were based on the year 2000 expenses to show the effect of profitability for future planning purposes. Actual grain harvested and sale prices each year of the study were used for sales.

For soybeans, the double disk system return was $124 per acre. No-till without cultivation was $161 per acre, therefore the long-term return to labor and management is $37 per acre more with no-till.

For sorghum, profitability was lower. With the double disk system, the return to labor and management was $85 per acre. The no-till soybean and sorghum rotation combined averaged $39.50 per acre more than the long-term double disk tillage system.

Side-by-side Tillage Comparison Trials

Side-by-side tillage comparison trials were conducted in Saline County by Extension Educator Randy Pryor in 1989 and 1990. Yield results were replicated within field and by multiple locations. The no-till versus conventional tillage trials (one or two tillage passes with a disk or field cultivator before planting) were in first year no-till fields or fields which had been no-till less than three years.

Dry conditions limited dryland crop yields in both years of the trials. No-till yields were higher than conventional tillage in all locations except for two trials. It is interesting to note all cooperators in this study, a decade ago, adopted no-till farming as a standard practice on their farms. Analysis of southeast Nebraska row crop cultivation costs in dryland fields has shown the combination of the cost of the operation and yield loss to be $28.00 per acre for sorghum. 

Summary

No-till farming is changing the face of dryland agriculture in Nebraska. Yield increases due to no-till farming have been documented in short-term and long-term studies as having cost savings. The long-term tillage study at UNL's Rogers Memorial Farm in Lancaster County has proven that with no tillage operations, better soil structure and higher yields, no-till is the most profitable tillage system.