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Strip Till for Field Crop Production

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Strip Till for Field Crop Production AE1370 (Revised) for Field Crop Production John StripNowatzki What is Strip Till? Till• Results in crop yields that are similar Agricultural Machine Systems Specialist or higher, compared with other tillage The trend among northern Plains NDSU Extension Service systems farmers is toward using less tillage to Greg Endres produce field crops with more residue • Reduces expenses by eliminating Area Extension Specialist/Cropping some primary and secondary tillage Systems left on the soil surface. Strip till is a field NDSU Extension Service tillage system that combines no till and full tillage to produce row crops. Strip Till and NRCS Jodi DeJong-Hughes Regional Extension Educator Narrow strips 6 to 12 inches wide are Conservation Incentives University of Minnesota tilled in crop stubble, with the area Strip tillage can be used to qualify for between the rows left undisturbed. the Natural Resources Conservation Often, fertilizer is injected into the tilled Service (NRCS) conservation manage- area during the strip-tilling operation. ment/no-till incentive programs. In dry conditions, The tilled strips correspond to planter To qualify for NRCS no-till incentive row widths of the next crop, and seeds programs, a Soil Tillage Intensity Rating reduced-tillage are planted directly into the tilled strips. (STIR) value of 10 or less is required. planting systems Strip tilling normally is done in the preserve moisture fall after harvest, but it also can be Table 1. STIR values for common in the seedbed, done in the spring before planting. tillage operations. enhancing uniform Operation STIR Advantages of Strip Till No tillage 0 germination and • Conserves energy because only part Double-disk opener planter 2.4 plant establishment. of the soil is tilled Strip till – coulter, 5-inch depth; • Reduces soil erosion because most 8-inch berm 7.7 of the soil remains covered with Strip till – shank, 7-inch depth; crop residue throughout the year 10-inch berm 15 • Releases less carbon into the Tandem disk, light finishing 19 atmosphere and maintains higher Vertical till 20 levels of soil organic matter Field cultivator, 6- to • Warms the tilled strips sooner in the 12-inch sweeps 23 spring to promote seed germination Tandem disk 32-39 and plant emergence Ripper 33 • Conserves soil moisture because most of the soil surface area is Chisel, twisted shovel or sweeps 42-49 covered with crop residue Moldboard plow 55-65 June 2017 1 • AE1370 Strip Till for Field Crop Production STIR is a numerical value calculated Equipment using RUSLE2, a computer model that predicts long-term average annual Equipment Components erosion by water. This model is based and Functions on crop management decisions Several strip-tillage equipment manu- implemented in a field. The NRCS facturers offer a variety of designs and assigns a numerical value to each features. Most equipment manufacturers tillage operation. STIR values range market machines with similar features, from 0 to 200, with lower scores including coulter blades, row cleaners, indicating reduced soil disturbance. tillage shanks, berm-building disks and packing wheels or conditioning baskets. Other benefits of low STIR values include increased organic matter Some strip-till equipment designs Figure 1. Carbon losses from content of the soil and improved tillage operations at Jeffers, Minn. include paired coulters or a large disk water infiltration rates. without a tillage shank. Most strip-till 06/21/07 PROSPER equipment manufacturers in the 50 northern Great Plains produce strip 45 Carbon Sequestration tillers with 30-inch or 22-inch row and40 exposed the greatest amount of soil, Effects allowing35 carbon previously stored spacing. A list of internet addresses of 30 strip-till equipment manufacturers is Soil organic matter plays a critical role in as organic matter or present as CO2 25 the global carbon cycle. Soil can act as a in the soil atmosphere to escape into included at the end of this publication. 20 major source for carbon released into the the atmosphere. 15 Coulter blades cut through the soil and atmosphere and a sink to store carbon. 10 residue ahead of the tillage shank. The 0 When carbon is stored in the soil, ManagingBEET BEANS Crop WHEAT Residue CORN coulters require mounting that allows flexible movement over stones. Some it is not released to the atmosphere as Residue from previous crops limits 07/03/07 PROSPER manufacturers use fluted coulters and greenhouse gases, particularly carbon evaporation50 from the soil surface and 45 designs with depth-control features with dioxide (CO2) and methane (CH4). Tillage maintains relatively high humidity levels 40 the coulters. The coulter size influences increases microbial action on organic in undisturbed soils at 90 to 100 percent, 35 operation in residue; larger-diameter matter stored in the soil and normally which30 are ideal for seed germination. coulters function better in heavy residue. increases the rate of decomposition Even25 with excellent seed-to-soil contact,Strips in fall Strips in spring that changes organic carbon into CO . 20 2 approximately 85 percent of the water Parallel linkages on each row unit 15 entering a germinating wheat seed is Soil organic matter is directly related 10 are desirable on strip tillers operated in the0 form of water vapor. on soil with large stones or rolling to soil fertility and positively correlated BEET BEANS WHEAT CORN topography because this linkage system with agricultural productivity potential. In dry conditions, reduced-tillage StripTilled Chisel Plowed allows row assemblies to move over Besides reducing greenhouse gases, other planting systems preserve moisture stones or uneven surfaces without advantages of increasing or maintaining in the seedbed, enhancing uniform interrupting accurate fertilizer a high level of soil organic matter include germination and plant establishment. placement on adjacent row assemblies. reduced soil erosion, increased resistance Crop residue also is a food source for to compaction, increased biological beneficial fungi, bacteria and insects. Row cleaners clear residue away activity and enhanced soil fertility. from the front of the tillage shank and Managed properly, the beneficial berm-building disks, leaving a clean, Because tillage results in soil carbon loss, aspects of maintaining high levels of tilled strip. Various manufacturers use identifying tillage methods that reduce crop residue with conservation tillage unique proprietary designs to clear the the amount of carbon released into the systems outweigh the negative aspects. tilled area. Row cleaners usually are atmosphere is important. A comparison Strip till leaves most of the previous mounted behind the cutting coulter and study of soil CO2 emissions following year’s crop residue on the soil surface, a few inches ahead of the tillage shank. moldboard plowing, disk ripping protecting new crop plants from wind and strip tilling conducted in 2005 damage during establishment and Strip-till equipment needs to be in Minnesota (Faaborg et al., 2005) continuing to protect the soil if the designed to meter accurately and determined that strip tillage maintained crop fails to establish due to drought or correctly place appropriate amounts more soil carbon than moldboard flood. Crop residue readily decays and of fertilizers in the tilled strips. plowing and disk ripping. is incorporated into soil by earthworms The ability to apply one or more liquid, Disk ripping and strip tillage and other invertebrates when the gaseous or dry fertilizers is an important released 53.2 and 82.6 percent less CO , growing crop canopy covers the design feature of strip-till equipment. 2 space between the rows. respectively, than moldboard plowing The tillage shank penetrates and loosens (Figure 1). Moldboard plowing disturbed soil, and normally is designed with a 2 • AE1370 Strip Till for Field Crop Production fertilizer injection tube to allow applica- Strip Till and GPS Guidance Crop Production With Strip tion of gaseous, liquid or dry granular Accurate equipment guidance is fertilizers during the strip-tillage Till Effects on Soil Residue important for strip tillage and the operation. Tillage depth is dependent On-farm research from 2010 through 2012 subsequent planting and spraying on the soil type and conditions, and in west-central Minnesota compared four operations, particularly in irregularly the specific crop to be planted. full-sized tillage systems with varying shaped fields. Strip tillage machines can crop residue levels in a corn-soybean Berm-building disks are mounted on be equipped with markers to facilitate rotation. University of Minnesota each side and 6 to 8 inches behind the accurate spacing of rows on each new researchers included chisel plowing tillage shank. The disks can be mounted round in the field, or global positioning with spring field cultivation, disk to mound the strip to promote moisture system (GPS) guidance can be used ripping with spring field cultivation, runoff and facilitate soil drying in the without markers. fall strip tillage and two passes with spring or, alternatively, mounted to GPS positioning accuracy of greater than a shallow vertical tillage implement. create a slight depression in the soil 6 inches pass to pass is recommended. to catch snow and rain to increase The type of tillage significantly affected Real-time kinematic differential soil moisture for the next crop. crop residue levels in this study. Strip correction (RTK) GPS is recommended tillage retained the highest crop residue Conditioning
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