This project seeks to analyze the impact of three grazing management regimes (see methods: LD-MIRG, HD-MIRG, and UHD-MIRG) on pasture productivity, soil health and farmer livelihood in the context of revitalization efforts on highly degraded grassland. We will implement three 2-acre treatments on land that heretofore has been conventionally managed for intensive hay production. We want to test whether increasing the stocking density and number of herd moves per grazing day can increase the stocking rate (i.e. carrying capacity) of the pastureland while improving soil health. We also want to economically assess the impact of employing batt-latch technology to implement each MIRG regime. We hypothesize that the batt-latch technology will greatly improve the economic efficiency of an intensive grazing system requiring multiple herd moves per day by way of minimizing farmer time and increasing stocking rate. We predict that the highest stocking density and greatest number of moves per day will correlate with the largest improvements in pasture productivity and soil health. Success in the context of this project will entail determining strategies for an economically efficient means of regenerating highly degraded grassland.
Our project seeks to better understand how high-density, management-intensive rotational grazing (MIRG) strategies can regenerate degraded agricultural land while improving farmer livelihoods. In 2009 we began managing 143 acres of compacted, degraded soils on a former conventional dairy farm and have since anecdotally seen vast productivity improvements with our MIRG of cattle. As we begin managing an additional 375 acres of former dairy land, we have an opportunity to level-up our grazing practices and better understand MIRG’s capacity to regenerate degraded land. Our project proposes using solar powered timed automatic gate release (batt-latch technology) for high-density MIRG to allow more herd moves per day while requiring less farmer time.
Commodity milk has greatly declined as a viable farming business due to market volatility, production practices, and a degraded landscape resulting in a high rate of farm closures and land transfers now with a significant increase predicted. Despite this market failure, the Northeast is well suited to grass-based ruminant production (e.g. beef) and productive grassland strategies that enhance soil health and economic efficiencies may help bolster surviving dairy farms while offering an economically viable business for new and existing farmers. We believe this study could have positive widespread impacts on the Northeast and offer a piece of the puzzle in keeping much of the land in question in agriculture while also regenerating degraded soils and impaired ecosystems.
The rich agricultural legacy of dairy farming is evident throughout Vermont and the Northeast even as the dairy industry continues its roller coaster of milk prices and production costs with what looks like a grim future. In the last decade, Vermont has lost nearly 1/3 of its cow dairy farms (Heintz, 2018). While many discussions around the dairy crisis focus on economic drivers and impacts, there is another element to consider: land use. Acreage devoted to hay, haylage, feed corn, and corn silage constitutes approximately 30% of agricultural land in Vermont (USDA, 2012). However, as dairies in the region close, demand for local hay and corn products is declining (Heintz, 2018). Amid the hardship, there is opportunity to explore strategies to improve the ecological health and economic viability of land previously tied to the dairy industry in the Northeast.
Land that has a long history of continuous hay and/or corn production is often highly degraded. Compaction from tillage and haying equipment impairs ecosystem hydrologic and nutrient cycles, with significant consequences for soil health. It is commonly understood that soil erosion and nutrient runoff are byproducts of highly degraded pasture or cropland and that they contribute to water quality issues (Waters 1995). Such externalities are abundantly evident in the new land that we began managing on June 1, 2018. The land was all conventionally managed for hay and corn production for many years. Consequently, the soil and surrounding agroecosystem are in extremely poor condition.
This project aims to better understand how management-intensive rotational grazing (MIRG) strategies can regenerate degraded agricultural land and improve farmer livelihoods. MIRG prescribes high stocking density and frequent grazing herd moves. However, many variables have not been adequately studied and ecologically optimal stocking density and daily herd moves in the context of pastureland regeneration remain uncertain. Consequently, we are motivated to explore these issues and to examine the economic viability of MIRG strategies in the context of grass-fed beef production. While MIRG has the potential to ameliorate ecological degradation, it requires significant time investment from farmers, which brings into question the economic viability of the strategy. Batt-latch technology offers a time-saving solution, but the application and impacts of this technology have not been rigorously examined.
Given this twofold focus, our project has broad applicability within the Northeast. As we have outlined above, there is likely to be an increasing amount of farmland available much of which is likely to have highly degraded soils and impaired ecosystems. Exploring ways to keep this land in agriculture while also regenerating agroecosystems and contributing to farmers’ economic livelihoods will be highly relevant for farmers throughout the region. Determining optimal grazing strategies that increase the resilience of both soils and farmer livelihoods for climate change adaptation would be widely valuable to farmers throughout the region. Our clay soils are typical of Vermont’s Champlain Valley and many other lacustrine and riparian soils throughout the Northeast that are potentially highly productive but present management challenges in the era of climate change.
Throughout its 10 years, Bread & Butter Farm has practiced MIRG with beef cattle for agroecosystem regeneration on its 143 acres of land permanently conserved through the Vermont Land Trust - land we have seen soil, pasture, and surrounding ecosystem health flourish in correlation with our MIRG practices. We now manage a total of 600 acres of owned and leased land that was historically intensively hayed and cropped or continuously pastured; as a result, inherited soil health is poor and pasture productivity low. With our expanded lands, we want to seize the opportunity to supplement our anecdotal observations with data that clarifies and confirms the interaction between MIRG strategies and regeneration of degraded land.
Our 50-head herd of 100% grass-fed Devon cattle are mostly born and raised on the farm. All beef, grossing over $60,000 annually, is sold on-farm direct-to-consumer in our farm store and CSA. Total farm gross annual income exceeds $400,000 with vegetables, pork, beef, resale products, events, and education.
Corie Pierce, farm owner, and Brandon Bless, animal and land manager, are full-time farmers responsible for a team of 4 year-round farmers and educators, a seasonal staff of 25, and all farm management decisions. These two individuals represent 35 years of experience managing farm operations, 15 years of college-level teaching to aspiring farmers, and hold natural resources undergraduate and graduate degrees and professional certificates. This experience is supplemented by our connection to the ALC, our technical partner. Dr. Ernesto Mendez, director of the ALC, brings 20 years of experience conducting agroecological and agroforestry research with smallholder producers. This connection will be vital in conducting and analyzing soil sampling to assess the impacts of our treatments on soil health.
Fencing and water equipment (~$1000) supplied by farm. October 2018/19 soil testing supported by ALC funds.
We conducted a three-treatment experiment to determine any variable soil and pasture health responses and economic analysis to different stocking densities and grazing period lengths. Our three treatments are outlined below.
Management-intensive grazing – prescribed pasture management that mimics wild ruminant herd patterns and grassland coevolution by using high stocking density, short grazing duration, and long grazing rest period to benefit both land and animal health and production (also labeled “mob grazing” or “intensive rotational grazing” or “adaptive grazing”)
Stocking density – pounds of animal live weight per unit of land – often per 1 acre (or hectare) and calculated from grazing cells smaller or larger than 1 acre
Animal unit – equivalent to 1000 lb live weight cow, and 2.5% body weight of plant dry matter consumption per day
Stocking rate – number of animal units able to graze on a unit of land as a function of plant dry matter
Grazing duration – amount of time a herd grazes and ruminates within a cell excluding sleep hours
Grazing cell – the fenced area of a single herd move
Grazing cycle – the successive grazing of the same land/cell over the year
Rest period – the amount of time between grazing cycles
Batt-latch – solar powered pre-set time released electric fencing gate that automatically opens successive grazing cells
Treatments were conducted on three approximately 2-acre areas located on newly acquired land. The three test plots were selected to minimize differences in elevation, slope, and soil characteristics; sites correspond to areas where we were able to collect baseline soil data in October 2018. Treatment areas were delineated and recorded using GIS mapping software via smartphone apps. Additionally, we employed GPS geolocation ground-truthing to verify coordinates of the treatment sites. The analysis, comparison, and final assessment of soil health and economic efficiency impacts were done in collaboration with our technical partners. We relied on the ALC’s guidance and access to data processing software (SPSS and R) to analyze variation in soil health indicators over the course of the project, determine whether changes are statistically significant, and assess how such changes correlate with treatments. The cattle herd represented approximately 60 animal units or 60,000 pounds live weight.
Treatment One, Low Density MIRG (LD-MIRG):
This treatment served as a type of a control, representing a much more traditional and conservative form of MIRG. Stocking density was held to approximately 30,000 pounds of animal live weight per acre. The cattle had access to a single grazing cell as the full approximately 2-acres for a available forage determined period. This treatment requires no additional moves, and therefore does not require the use of batt-latches.
Treatment Two, High Density MIRG (HD-MIRG):
This treatment explored a higher stocking density, which corresponded to smaller grazing cell size and multiple moves per day. We used an approximate stocking density of 100,000 pounds of animal live weight per acre. To achieve this, cattle grazed on cells approximately 0.6 acres in size, and were move through three cells over the course of a grazing day with an estimated 6.5 hour grazing duration per cell. Moves were facilitated by the use of two batt-latches.
Treatment Three, Ultra High Density MIRG (UHD-MIRG):
This treatment applied an ultra high stocking density, the impacts of which have not been sufficiently explored in scientific research but in our experience have shown the most promising results. We used an approximate stocking density of 500,000 pounds of animal live weight per acre. This ultra high stocking density was achieved through the construction of many very small grazing cells and a very short grazing duration. Cattle were moved through 15 cells in a grazing day with an estimated 1.5 hour grazing duration per cell (approximately 4 hour grazing duration overnight). Moves were facilitated by the use of seven batt-latches (which will be recycled, so to speak, mid-day to keep equipment costs manageable during this stage of assessing efficacy of this technology).
For each of the three treatment sites we already had a composite sample subject to the Cornell Assessment of Soil Health at the Cornell Soils Lab, and we have baseline, pre-grazing data on penetration resistance, and bulk density prior to beginning our MIRG regimes. In October of 2019, at the end of the grazing season for the treatment areas, we conducted successive rounds of soil sampling to assess change in soil health. This included penetration resistance, bulk density, biological assessment and a second round of analysis through the Cornell Soils Lab or another soil testing service. We were not able to conduct water infiltration tests.
All treatment area grazing cells in each grazing cycle were GIS delineated and photo-recorded for pre- and post-grazing, and grazing hours were recorded. We calculated the pre- and post-grazing dry matter in pounds per acre using a grazing stick for each grazing cell in each grazing cycle. We also conducted observations of pasture plant diversity in each treatment area.
Farmer time was recorded for all work associated with moving the herds through the treatment sites. This included time to set up and manage treatment areas (e.g. fencing, batt-latches, water, minerals) before, during and after grazing days in each grazing cycle. The LD-MIRG treatment site was indicative of the cost of farmer time spent on management without the application of batt-latch technology; we could then extrapolate outward to approximate the amount of time spent moving herds without the batt-latches for HD and UHD regimes. This gave us a sense of both the time and cost savings associated with applying batt-latches in the HD-MIRG and UHD-MIRG treatments.