Table 8.2 shows the crops, costs and revenue for an example 200-acre farm transitioning to a sod-based rotation with livestock grazing. Prior to the first year, the farm used a standard conservation rotation with two-thirds of the farm in cotton and one-third in peanuts. The net returns for the standard conservation rotation are shown at the top of Table 8.2. The net returns during the transition are compared to the returns for a standard conservation rotation with an oat cover crop each winter.
For the first year of the transition, the 200-acre farm is divided into four 50-acre fields. A 200-acre farm is an economical size for small farms with limited available labor. The first year of the transition has 50 acres in bahiagrass, 100 acres in cotton and 50 acres in peanuts. The following years have 100 acres in bahiagrass, 50 acres in cotton and 50 acres in peanuts. Grazing the bahiagrass can begin 10–12 weeks after planting in the first year. The example in Table 8.2 assumes that grazing does not occur until the second year.
In the first year, net returns are low due to establishment costs for the bahiagrass, fewer acres of cash crops and no income from grazing. However, profits are still greater with the transitioning farm than with the standard conservation rotation. Revenue generated in the first year with bahiagrass assumes two harvests of hay, baled either square or round. Livestock grazing is added the second year and significantly increases income. Third-year returns are more than three-fold higher than the standard rotation due to the expected yield increase for peanuts. Depending on conditions, third-year net returns can be two to six fold higher than the standard rotation. In year four, net income is also more than three fold higher than the standard rotation. Fourth-year net returns can be three to six fold higher than the standard rotation. Additional increases in year four are due to increased cotton yields. The net income in the fourth year is the projected annual net income for this example.
Returns are greater when livestock graze on first-year bahiagrass throughout the season, as observed on a 99-acre farm in Florida. In this example, 81 head of livestock (cow/calf pairs) grazed on 49 acres of second-year bahiagrass as well as 49 acres of first-year bahiagrass. In another example, more livestock were supported on a 172-acre farm, with as many as 200 head on winter grazing in the sod-based rotation. Many more animals can be raised in a year-round cow/calf operation.
These examples show that livestock are important for profitability. Contract grazing of stocker livestock in the winter can achieve returns of $427–$1,373 per acre . Research has also shown that livestock can add profitability to cropping systems without reducing the yield of winter wheat or the following sorghum row crop . However, increased peanut and cotton yields provide the biggest economic impact in a sod-based rotation. When livestock are in the system, some of the increased yield is due to improved nutrient cycling .
If a grower does not have livestock, there may be opportunities to increase profitability by selling bahiagrass or bahiagrass seed. Many small row-crop farmers in the Southeast have livestock herds of fewer than 100 head and may buy hay instead of investing in hay planting and harvesting equipment. Or, they may contract graze their livestock on both winter cover crops and summer bahiagrass. These are possible market opportunities for farmers who want to use a sod-based rotation without owning livestock.
Finally, one of the aspects of increasing net return in this system is the year-round use of land and labor. Year-round use of the land provides opportunities for better returns. While labor requirements and costs increase, net returns typically do as well.
Livestock is one of the missing links in developing sustainable systems . Livestock prices fluctuate, so there is potential for occasional high income with livestock in the system. This justifies including perennial forages in the rotation. A rotation with sod, livestock grazing, row crops and winter small grains is a highly productive, economically sustainable, energy-efficient and environmentally friendly farming system. This rotation has the potential to improve the profitability of medium- and large-scale farms while also offering an attractive model to small family operations and beginning farmers.
If economics is the dominant factor when deciding whether to adopt a sod-based system, compare the system to a standard conservation rotation, even though such an analysis can be complicated . Income is lost when the area allocated to the most profitable crop is reduced. However, the effect on the bottom line ends up being less severe than the lost income because the grass requires fewer inputs in terms of water, fertilizer, pesticides, labor and energy. In addition, a diversified, sod-based rotation offers economic risk management with unpredictable or extreme weather. If only half the farm is in cash crops during damaging weather, losses are reduced compared to a standard conservation rotation where the farm is entirely in cash crops. A deeper root zone with the sod-based system provides access to more soil water that reduces the impact of short-term drought. Soil improvements with a perennial grass in the rotation improve growth and yield of the main cash crop.
The website for the North Florida Research and Education Center (NFREC) has an interactive business model for evaluating the feasibility of a four-year, sod-based rotation. The business plan is presented as an Excel spreadsheet with several tabs. The tabs include detailed cost estimates for bahiagrass, row crops, cover crops, livestock, irrigation and labor. Costs for a standard conservation rotation and a sod-based rotation are included. A summary sheet brings cost and income information together into a four-year business plan. Real farm data can be entered into the spreadsheet to determine if a sod-based rotation is feasible for the farm. The website address is https://nfrec.ifas.ufl.edu/sod-rotation/. The business plan changes with time as more research data is added.