Part 1, Section 1: Soil Management
TILLAGE MANAGEMENT
Status of Soil Tillage in Pennsylvania
Every two years, the USDA-NRCS, in collaboration with other agencies, performs a crop-residue survey that is published by the Conservation Tillage Information Center (CTIC) located in Lafayette, IN. The CTIC defines various tillage systems in its survey. See Box 1.1-2.
| Source: National Crop Residue Management Survey, Conservation Tillage Information Center. | |
| Conventional tillage | Tillage systems that leave less than 15% residue cover at planting, or less than 500 lbs/A small grain residue equivalent throughout critical erosion period. |
| Reduced-till | Tillage systems that leave 15-30% residue cover at planting or 500-1000 lbs/A small grain residue equivalent throughout critical erosion period. |
| Mulch till | Full-width tillage system that disturbs the whole soil surface prior to and/or during planting. Leaves more than 30% residue cover at planting or more than 1,000 lbs/A or small grain residue throughout critical erosion period. |
| Ridge till | The soil is left undisturbed from harvest to planting except for strips up to 1/3 of the row width. Planting is completed on the ridge and usually involves the removal of the top of the ridge. Residue is left on the surface between the ridges. Ridges are rebuilt during cultivation. Ridge till is sometimes referred to as plant-till. |
| No-till and Strip-till | The soil is left undisturbed from harvest to planting except for strips up to 1/3 of the row width. Cultivation may be used for emergency weed control. No-till is sometimes referred to as direct seeding, slot planting, zero-till, row-till, and slot-till. |
Conservation tillage is any tillage system that leaves more than 30 percent residue cover at planting, or more than 1,000 lbs/A of small-grain residue throughout the critical erosion period. Conservation tillage is the sum of no-tillage, ridge tillage, and mulch tillage. In Pennsylvania, the percentage of conventional tillage remained almost constant the past 14 years at approximately 50 percent of planted acres (Figure 1.1-3). The area of reduced tillage has also remained constant at approximately 17 percent of planted acres. The total percentage of nonconservation tillage was 64 percent in 2004. The area of mulch tillage decreased from 19 percent in 1990 to 11 percent in 2004. The largest portion of this decrease occurred between 1998 and 2004 and seems to be a continuing downward trend for mulch tillage. The area of no-till steadily increased from 18 percent to 24 percent between 1990 and 2004. The crop residue survey therefore indicates that there has been little change in tillage management over the past 15 years.
The percentage of the planted acreage per county that was under nonconservation tillage (conventional and reduced tillage) is presented in Figure 1.1-4. In Figure 1.1-5, the percentage of no-till in each county is presented. The counties with the largest percentage of no-till are Adams, Blair, Clarion, Dauphin, Franklin, and Northumberland. The total planted acreage is very small, however, in Blair and Clarion Counties. In terms of acreage, the top no-till counties are York, Franklin, Northumberland, Chester, and Adams. The higher adoption of no-till in some counties is partially due to climatic and soil-related factors, as well as the type of farming system. Unfamiliarity or previous negative experiences with this technology may also explain differences in no-till adoption. In the next section, we will discuss a tillage recommendation zone classification for corn in Pennsylvania.
