Cover crops have been gaining a reemerging acceptance over the last decade, with very few producers disagreeing about the potential soil health benefits of adding cover crops to their farming operation. However, with low commodity prices producers are trying to reduce expenses on inputs, especially on inputs with a varying or unknown return. This leaves cover crops in a peculiar place, with a somewhat difficult to measure or unknown monetary return from increases in soil health, fertility, and nutrient availability. This can leave some producers questioning, “How can I use cover crops and see an immediate return on my investment?” Recent research from separate departments at South Dakota State University are pointing towards one answer, livestock integration.
South Dakota Farm Survey Findings
During Spring 2017, we conducted a farm level survey on adoption of conservation practices and precision technologies in South Dakota. Of the nearly two hundred survey respondents, mostly from the Eastern half of South Dakota, 51% raised cattle in some form, either beef or dairy. Of those livestock producers, 94% grazed crop residue, but only 39% grazed cover crops. Additionally, of the total respondents, 31.3% used cover crops in their operation in 2016, with 64.5% of them using cover crops with livestock integration.
REASONS FOR ADOPTING COVER CROPS
The producers were asked to score the importance of several reasons influencing their cover crop adoption decisions as follows: (1) Not Important, (2) Slightly Important, (3) Moderately Important, and (4) Very Important. We also asked non-adopters to score a list of reasons why they chose not to use cover crops on their operations. The scores and rankings for each group presented in Table 1 and Table 2 show that “Improves soil health”, “Increases farm productivity”, and “Improves water availability/water conservation” scored high among adopters, while “Planting time conflicts with harvest of cash crops” and “Satisfied with current practices” score high among non-adopters. It should be noted that the all of these rankings were based off of the producer’s perceptions. For example, while non-adoption producers ranked “Not Profitable” 4th on the rankings with a score of 2.37, they likely cannot substantiate the score. One interesting finding was that “Helps with livestock integration” was relatively lower on the list for all cover crop adopters. However, as we stated before, only 64.5% of cover crop adopters used them with livestock integration, primarily because they don’t have livestock. By separating out the segment of producers without livestock, the difference in adoption reasons between the aggregate of cover crop producers (Table 1) and those using with livestock emerges (Table 3).
Livestock Integration & Farm Profitability
Comparing the results from Table 1 and Table 3, the top three reasons remain the same, with scores that are virtually identical making the rankings a formality. However, “Helps with livestock integration” jumps in ranking and increases its score by approximately 18%. More striking is the increase in “Increases farm profitability” jumps in ranking from 8th to 4th and the score increases by over 52%. Those producers who are integrating livestock see value in doing so. Producers are doing so for profit motivations as well. The large increase in the score for “Increases farm profitability” tells us livestock integrators are using cover crops for the same top reasons as other cover crop adopters, but are doing so with profitability as a top driver as well.
REASONS FOR NOT ADOPTING COVER CROPS
The data in Table 2 also tells us the main reason for not using cover crops for non-adopters is timing conflicts with cash crops. Corn and soybeans can present challenges for using cover crops, especially with livestock integration. There are opportunities to seed cover crops after corn silage and soybeans, but growth can be limited by less heat units and daylight, as well as moisture availability. However, small grains do present an excellent opportunity to combine the use of cover crops and livestock integration. Producers using cover crops after small grain production maximize forage yield potential due to a longer growing season and a greater potential for precipitation, while still harvesting a cash crop.
Profitability Following Small Grains
The SDSU Southeast Research Farm in Beresford has been collecting data on cover crop forage yields after small grains for the last several years. Data collected from 2010-2016 of dry matter (DM) after small grains show an average of 2,262 lbs. DM/acre. The range has been anywhere from 0 (2012) to 4540 (2013) lbs. of DM/acre. There is an upward trend in the forage yields, with the last 4 years averaging 3,031lbs./acre or about 1.5 DM tons/acre (Sexton, 2017). Using the yield estimate of 1 to 1.5 DM ton/acre, and assuming a utilization rate of 50% (which can vary depending on the intensity of grazing management), actual feed available can range from 0.5-0.75 DM tons/acre. If using a hay DM value of $90/ton, the potential direct gross return could be between $45-$67.50/acre. Most cover crop mixes will cost between $10-40/acre, depending on the type and complexity of the mix and seeding expense. As shown above, the forage value alone can cover seed costs for cover crops. Another way to evaluate this is on a per head basis. The researchers at the Southeast Research Farm conducted some field trials that focused on the different options for grazing livestock on cover crops during the 2016 crop year. One specific treatment was planting a cover crop after small grains, wheat and rye. A cover crop blend was planted on July 21, 2016, consisting of radish, turnips, peas, lentils, oats, sorghum, and millet. Grazing began on September 17 and lasted through October 3, with 28 head of yearling replacement heifers on those 3.5 acres before being moved. This resulted in 448 head days or 128 head days per acre (Rops et al., 2016). To put this into perspective, by scaling these results up to an 80-acre field, if producers grazed from October 1 – November 30 (61 days), and assuming no additional forage growth potential, this field would support roughly 50 Animal Units Monthly (AUM).
Other variable expenses should be considered as well, such as costs to prepare the ground and seed the cover crop, fencing costs, and labor. The seeding costs are dependent on the capabilities of the producer. Fencing is also dependent on the producer’s situation. If fields already have the fencing available, then the maintenance cost is very small. If fencing is not available, there are options for temporary, high tensile fences that can be installed and removed rather quickly and easily. This will add expense and increase labor hours, but if this is part of a long-term strategy, the capital costs could be spread out over several years. To best utilize the forage, it is suggested to paddock the field and mob graze to minimize trample loss. These additional costs could be offset by the value of not having cattle in a yard and reducing the time spent feeding, bedding, and cleaning, all of which incur machinery and labor costs. By grazing the animals on cover crops into late fall, producers are able to have their livestock feed themselves, spread their own manure, and maintain their own bedding situation.
Impact on Corn Yields
The Southeast Research Farm also conducted some research pertaining to corn yields following cover crop use and livestock integration. The conclusions from their work highlighted three main points of interest. First, there was no detrimental effect to the following year’s corn yield after any of the cover crop mixes they used. Second, there appears to be a positive correlation between corn yields and the proportion of broad leaves in the cover mix, and heavy grass mixes had a neutral impact on yields. Third, a weak trend was noticed of the following corn crop is need for less nitrogen, but the authors suggested further research should be done to substantiate the findings (Sexton et al., 2016). These findings add support to the potential benefits of cover crop use, adding additional value that will improve producers’ bottom line.
The Bottom Line
These are just the a few of the clearly measurable benefits of cover crop use with livestock integration. Other potential benefits include increased soil fertility, reduced weed pressure, and an overall increase in soil health from the synergy from adding livestock and a polyculture of plant species back into the soil. For a livestock producer who wants to start using cover crops in his/her operation, adding cover crops with livestock integration is a practice with minimal risk, but with the potential to benefit the overall success of the whole farming operation.