Written collaboratively by Tong Wang, Hongli Feng, David Hennessy, and Mary Doidge.
An increase in land conversion from grassland to cropland in the United States has attracted attention in recent years. According to Claassen et al. (2011a), grassland to cropland conversion is concentrated in the Northern Plains, including Kansas, Nebraska, North Dakota and South Dakota, which encompasses only 18% of U.S. rangeland but accounted for 57 percent of U.S. rangeland to cropland conversion during the study period of 1997 to 2007. Focusing on land cover data in the Western Corn Belt, Wright and Wimberly (2013) also pointed out that grassland conversion was mostly concentrated in the Dakotas, east of the Missouri River and between 2006 and 2011.
Along with the trend in land conversion, we have seen a dramatic increase in harvested corn and soybean acres. Both crops doubled from about 2.5 million acres in 1995 to about 5 million acres in 2015 as shown by Figure 1. While acreage in wheat and Conservation Reserve Program (CRP) also declined, their combined reduction totaled about 1.4 million acres which was much less than the combined increase in corn and soybean acres in the same 20-year period. This implies that significant corn and soybean acres likely came from non-CRP grass covers.
Grassland conversion and the environment
Grassland to cropland conversion raises concerns due to its many potential environmental implications. First of all, the conversion is damaging for many grassland-dependent species, which include North American duck species that nest in the area, grassland songbirds and prairie butterflies. In addition, increased use of fertilizers and chemicals on cropland, and elimination of buffers that filter farm runoff could cause secondary effects such as downstream water pollution (Faber et al., 2012). Finally, the substantial amount of carbon and wide array of ecological services provided by well-managed grasslands will be lost upon conversion to cropland. Soil microorganisms, which are important to the quality of the grassland habitat, cannot be readily restored. In addition, reductions in soil carbon sequestration caused by the conversion can take more than three decades to repay the biofuel substitution away from fossil fuels (Gelfand et al., 2011).
Figure 1. Trends of major crops harvested acres and CRP in South Dakota in the last 20 years. Data Source: USDA National Agricultural Statistics Services (NASS) and Farm Service Agency (FSA).
Rotational grazing and grassland conversion
Numerous public policies and regulations as well as private initiatives have been proposed to curtail or reverse grassland conversion. By reducing expected profit from cropland production, penalty-type interventions can discourage landowners from grassland conversion. One example is the Sodsaver provision in the 2014 farm bill, which will reduce premium subsidy rate by 50 percent for the first four years upon converting from native grass to cropland (Miao et al., 2016). According to Claassen et al. (2011b), Sodsaver can reduce grassland conversion rate by up to 9 percent.
Different from penalty-type, reward-type interventions aim to increase profit from grassland cover such as creating a monetary reward for carbon credit generated on working grassland. While both types of intervention will help reduce the grassland conversion, producers gain more from reward-type than from penalty-type interventions. One such example is grassland easement through which landowners are paid to keep their land in grass. Relative to land acquisition, easements are a cost-effective way for government agencies and non-government organizations to protect critical grasslands. As of 2011, the US Fish and Wildlife Services have protected over 2 million acres of grassland through easements in the Prairie Pothole Regions of the Dakotas. (USFWS 2011). In fact, easements could be combined with efficient grassland management practices to enhance landowner income and promote grassland conservation.
Promotion of intensive rotational grazing practices might serve as another reward-type intervention for ranchers to increase profit from the rangeland and pasture, therefore potentially avoiding grassland conversion. Rotational grazing, also known as cell grazing, management intensive grazing and holistic managed planned grazing, has been recommended since the mid-20th century as an important tool to adaptively manage grazing land ecosystems. Under rotational grazing, the rangeland/pasture is subdivided into smaller areas, one paddock is grazed at a time while the other paddocks recover. There is published and anecdotal evidence from producers that, if applied appropriately to produce most advantageous results, rotational grazing can lead to improved forage and livestock production (Stinner et al., 1997; Teague et al., 2013).
Focus group meetings of landowners conducted in March, 2016 in Mitchell, Huron, and Aberdeen, South Dakota and Jamestown, North Dakota1offered some preliminary information regarding the link between rotational grazing and land use conversion. Out of 76 attendees at the focus groups, 51 responded to the question on whether rotational/management intensive grazing was practiced on their farm. Of the 51 who responded, 28 answered “Yes” to the question while 23 answered “No” (Table 1).
Table 1. Relationship between rotational grazing and land use conversion decisions over 2006-2015.
|Percentage of a farm’s converted acres out of its total acres|
|Rotational Grazing||Number of farmers||Grassland to Cropland||Cropland to Grassland|
Multi-year experimental data collected from Iowa and Missouri demonstrated that net returns from grassland managed under intensive rotational management practice may surpass those from rotational cropping system, especially on highly erodible land (Riley et al., 1993; Moore and Gerrish, 2003). Therefore, rotational grazing adoption could serve as an option that potentially boosts profit on rangeland without converting to cropland. Our focus group findings reveal a similar pattern regarding land use conversion, where the difference between the two groups is statistically significant (Table 1). For those who practiced rotational grazing on their farm, 1.4% of their total farmland acres on average were converted from grassland to cropland over the past decade. On the other hand for those who did not use rotational grazing, 4.0% of total acres on average were converted from grassland to cropland during the period. Regarding cropland to grassland conversion, the opposite trend was observed. Compared to the 0.7% conversion rate among non-adopters, those who adopted rotational grazing have converted a higher proportion of cropland to grassland, namely 3.4%. Therefore rotational grazing may have an additional environmental implications in that it may encourage the maintenance of grass-based production systems.
Rotational grazing adoption and farm characteristics
Of the producers who adopted rotational grazing practice, we can see they are likely to have a larger herd. In addition, significantly larger percentage of the farm acres is used as grazing land (Table 2). It seems that those who devoted a larger share (more than 40%) of their land to cattle production are more likely to adopt rotational grazing practice, while non-adopters had on average less than 30% land used for cattle production.
Table 2. Relationship between rotational grazing adoption and farm practices.
|Rotational Grazing||Number of farmers||Average Herd Size*||Percentage of farm acres as grazing land|
|*: These are categorical values: 3 corresponds to a herd size of 51-100 and 4 correspond to a herd size of 101- 200.
The benefits of rotational grazing adoption have been increasingly recognized in the policy arena. Starting from September 2015, the CRP-grassland initiative was established to provide participants with up to 50 percent of payment for practices such as cross fencing, to encourage rotational grazing (USDA, 2015). Like other voluntary programs, success of the CRP-grassland initiative is contingent on producers’ willingness to participate. Whether the CRP-grassland initiative gives producers sufficient incentives to adopt rotational grazing in the short and long term remains unknown. It therefore presents a strong need to analyze the benefits of rotational grazing and the determinant of adoption decisions among producers with different farm characteristics.
- Claassen R., F. Carriazo, J.C. Cooper, D. Hellerstein, K. Ueda (2011a) Grassland to Cropland Conversion in the Northern Plains: The Role of Crop Insurance, Commodity, and Disaster Programs. Economic Research Report No. ERR-120.
- Claassen R., J.C. Cooper, F. Carriazo (2011b) Crop insurance, disaster payments, and land use change: The effects of Sodsaver on incentives for grassland conversion. J Ag Appl Econ 43:195–211.
- Faber, S., S. Rundquist, and T. Male (2012). Plowed Under: How Crop Subsidies Contribute to Massive Habitat Losses. Environmental Working Group.
- Gelfand I., Z. Terenzio, P. Jasrotia, J. Chen, S. Hamilton and G. Robertson (2011). Carbon debt of Conservation Reserve Program (CRP) grasslands converted to bioenergy production. Proc Natl Acad Sci 108(33):13,864–13,869.
- Miao R., D.A Hennessy, and H. Feng. (2016). The Effects of Crop Insurance Subsidies and Sodsaver on Land-Use Change. Journal of Agricultural and Resource Economics
- Moore, K., and J. Gerrish. 2003. Grazing systems vs. row-crop enterprises. ANGUSJournal, 93-95.
- Riley, B., C. Nelson, K. Kaetzel, D. Thomas, M. Duffy, and D. Strohbehn. 1993. An economic Comparison of Rotational Grazing Systems to eight crop alternatives and the CRP Option for highly erodible land in southwest Iowa. 1993. Beef-Sheep Report, As-622, Iowa State University.
- Stinner, D. H.; Stinner, B. R.; Martsolf, E. (1997). Biodiversity as an organizing principle in agroecosystem management: case studies of holistic resource management practitioners in the USA. Agric. Ecosyst. Environ. 62, 199-213.
- Teague, R.; Provenza, F.; Kreuter, U.; Steffens, T.; Barnes, M. (2013). Multi-paddock grazing on rangelands: why the perceptual dichotomy between research results and rancher experience? J. Environ. Manage. 2013, 128, 699-717.
- U.S. Department of Agriculture (USDA), (2015). USDA announces conservation incentives for working grass, range and pasture lands, News Release No. 0204.15.
- U.S. Fish and Wildlife Service. (2011). Land Protection Plan—Dakota Grassland Conservation Area. Lakewood, Colorado: U.S. Department of the Interior, Fish and Wildlife Service, Mountain–Prairie Region. p169.
- Wright, C.K., and M.C. Wimberly (2013). Recent land use change in the Western Corn Belt threatens grasslands and wetlands. Proc Natl Acad Sci 110(10):4134–4139.
1The focus group meetings were partially supported by a research grant (FAIN: G15AP00086; CFDA: 15.820) from the Department of the Interior (DOI), North Central Climate Science Centers (NC CSC) and from the National Climate Change and Wildlife Science Center (NCCWSC). The views in this article are attributable solely to the authors.