The winter months before cash crop planting are not nearly as busy as the fall, but there are tasks to accomplish such as planning, scouting, maintaining equipment and purchasing supplies. It can also be a time to diversify the farm with livestock grazing.
Plan Crop Rotation
A good crop rotation spreads risk, breaks pest cycles and improves yields. Although cropping decisions are strongly driven by the market, planning ahead for a crop rotation can help maximize profits over the rotation cycle. Now is a good time to decide the cash crops and cover crops to be grown on each field and to look ahead to the next cover crop. For example, follow cereal cover crops with soybeans or other legumes. Grow clover or other legumes before cereal cash crops or corn.
Figure 4.1 shows a crop rotation planner for a two-year rotation of field corn>rye cover crop>cotton>crimson clover cover crop. This rotational sequence can be repeated for a four-year rotation. The horizontal rows of 52 boxes in Figure 4.1 represent one year and each box represents one week. Colored cells represent the time each crop is in the field from planting to harvest, or termination in the case of cover crops. Table 4.1 includes the days-to-maturity (DTM) data used to determine the number of weeks the crops will be in the field. Note the recommended three weeks between termination of the rye cover crop and planting cotton in year two.
FIGURE 4.1. An example of a crop rotation plan.
Construct your own crop rotation planner using Figure 4.1 as a guide. This can be done with a spreadsheet, or your can make a template on paper and copy as needed. Compare alternative rotation scenarios using the days to maturity (DTM) data in Table 4.1 or local knowledge as a guide for planting and harvest or termination timelines. If winter grazing is being considered, block out sufficient weeks based on local practices or block out 15 weeks on the planner. You can use the crop rotation planner to define a rotation for the next three to four years for each field. It can be updated as more information becomes available.
Graze Livestock
Diversity is often the key to a successful farm operation, and combining livestock and field crops is an example of a diversified operation. Rye or ryegrass as a winter cover crop is excellent for livestock grazing. Fields must be fenced. Grazing begins in late fall or early winter when plants are 6–8 inches high [1]. The forage variety and planting date influence when the field is ready for grazing. If the cover crop is planted from late September to early October, normally there will be enough growth by December to begin grazing. Grazing can continue until March. Once cattle are removed, the crop will recover and provide adequate cover for summer cash crops. See Chapter 8 for more detail on incorporating livestock into conservation tillage systems.
Manage Nitrogen
Decisions to topdress winter cover crops with nitrogen are based on the cover crop, the previous crop, the next crop, soil types, field experience and the weather. For example, if cover crops follow a legume such as peanuts, there is usually no need to apply nitrogen. Cereal cover crops are often given a sidedress of nitrogen in late winter to get maximum biomass production. Late-planted cover crops and those affected by cold temperatures sometimes need nitrogen to stimulate growth. The need for nitrogen applications will vary. Do not fertilize cover crops if they are intended to scavenge for nitrogen. Consider each factor and soil test results to determine rates and timing.
Control Winter Weeds
Scout for weeds in January. There may be weeds emerging that can affect winter growth of the cover crop and can compete with the following cash crop. In the Southeast, scout for these common weeds: horseweed, wild turnips, wild radish and cutleaf evening primrose. Even though these weeds are winter annuals, they will grow through spring planting and compete with cash crops. These weeds are hard to control after crops are planted.
Scout for and Control Insects
There are not many insects to be concerned about in cover crops, although aphids can be an issue in small grains and legumes. Begin scouting for aphids a few weeks after cover crop planting.
Aphids do most of their damage in the early-growth stages of cover crops.
Prepare Equipment
Service equipment for terminating or harvesting winter crops and for planting spring crops. Before spring planting, use roller/crimpers for terminating cover crops and harvesting equipment for winter grains or seed patches. Service planters, strip-till rigs, sprayers and other needed equipment so they are ready for spring planting.
Purchase Spring Planting Supplies
Late winter is a good time to make plans for the cash crop. Get the best varieties by purchasing seed early. Make plans to buy fertilizer and pesticides, too.