The crops commonly grown in the Southeast United States do well in the humid, temperate climate and low-organic-matter soils predominant in the region. Yields and soil quality are improved when these crops are part of a rotation. Production practices such as timing, tillage, pesticide application, irrigation and cover crops will vary based on cash crops in the rotation. Cover crops may include a single species or a mix of species. Common cover crops include grasses for nutrient scavenging and carbon addition, brassicas with deep taproots to break up hardpans, and legumes to add nitrogen.
This chapter discusses cash crop selection and crop rotations in the Southeast. Table 7.1 lists the crops grown in the Southeast from highest acreage to lowest. In this chapter, Southeast refers to the states represented in Table 7.1: Alabama, Florida, Georgia, Mississippi, North Carolina, South Carolina, Tennessee and Virginia.
When selecting crops and planning rotations, use strategies that mitigate the causes of yield reductions. The book Farm Management, published in 1918 [24], listed these main causes of reduced productivity:
- Fertile surface soil is carried away by wind or water erosion.
- Soil no longer has the water-holding capacity to supply plant needs.
- Soil ceases to provide a favorable environment for soil organisms.
- Nitrogen is carried away in drainage water.
- Monoculture cropping exhausts the available supply of plant nutrients.
- Organic matter is lossed: the most frequent cause of decreased yields.
- Alkali accumulates in the soil: a common reason for reduced yields in arid regions.
The same soil quality and crop production issues are at the forefront of agriculture today and need to be considered for optimal yield and environmental sustainability. Fortunately, problems in the Southeast, such as decreased crop yields and degraded soils, can be overcome with conservation agriculture systems, integrated nutrient and pest management, new technology and better crop selection.