The 2014 Planting Season Begins Now with Proper Residue Spreading
Posted: September 24, 2013
No-tillage crop production requires more advanced planning than tillage farming. In fact, no-till planting in the spring of 2014 begins now! It is very important to distribute crop residue evenly to guarantee excellent crop results next year. If residue is not distributed uniformly behind the combine it becomes very difficult to correct this later (Figure 1).
Figure 1. Uneven crop residue distribution will result in
poor no-till stands
Unevenly distributed residue causes a number of problems in no-till:
- Hairpinning and variable seed depth. Windrows and piles of residue will cause unsatisfactory planter performance next year. Variable depth placement of seeds, and hairpinning will occur. The planting units may even be riding over excessive residue, unable to penetrate the soil. This causes seeds to be dropped at the soil surface. Planters with disk openers are most susceptible to these problems.
- Uneven emergence. Even if seeds are placed accurately, an excessive mat of residue directly over emerging plants may cause plants to be injured, causing poor emergence. Patches of bare soil intermixed with thick residue cover will cause unevenness in soil temperature and moisture which will also affect emergence.
- Increased pest pressure. Certain insect pests and rodents just love to live in those thick patches of residue.
- Weed control problems. Weed seeds and grain lost through the combine will be concentrated in the residue patches. Concentrated weeds and volunteer crop plants are difficult to control. Herbicide effectiveness will be compromised because the herbicides don’t reach the soil.
Right now may be a good time to take a look at the spreader behind your combine. Distribution is very important, especially when you get a bumper crop. Suppose this fall will give you a 200 bushel/A corn yield, which weighs 9400 pounds oven dry. That means there will be almost 5 tons/A of corn stalks and chaff standing in the field (Figure 2a). If you have a 6-row combine without a spreader most residue will end up in a 5 foot swath. You will have accumulations of up to 9 tons of residue in that swath next to strips of bare soil (Figure 2b). A poorly working spreader gives intermediate results (Figure 2c). If you really want to do a good job you want to install both a residue and chaff spreader on the combine (Figure 2d).
Figure 2 a-d. Good corn residue distribution is essential for successful no-till.
There are combine straw spreaders with rotating blades or batts to deflect coarse particles. Chaff may need to be spread in addition to the coarse material with spinning disks, rotating batts, or air conveyance systems such as axial fans. Chaff is lightweight, easily deflected by wind, and difficult to move very far by mechanical means. Fans which create air flow to carry the chaff are more effective although their performance may be reduced by wind.
If your spreader has batts, it is important to replace them if they have rounded edges. Square edges on new rubber batts will increase spreader width. Adding more or longer batts or increasing the rotational speed improves residue distribution. Straw choppers also distribute residue. Long, angled deflector blades and increased rotational speed improve the spreading action of straw choppers. If chopped residue is not uniformly spread it makes denser windrows than unchopped residue. Contact your dealer for spreader options on your combine.