2012 Annual Report for LNC11-338
Mob Grazing Increases Efficiency and Profitability of Livestock Production
Summary
The mob grazing study was initiated in 2012 with 9 cooperating producers scattered throughout South Dakota. Baseline soil data was collected in spring 2012. Vegetation data was collected at each site. A tour was held at one of the sites in July to discuss implementation and data collection with the producer and researchers. Economic and production records were collected via interviews on 6 of the 9 producers. In December, an annual meeting was held with all the producers and researchers. We discussed the first year results and made plans for future tours.
Objectives/Performance Targets
1)Establish 9 mob grazing sites across South Dakota, collect spring baseline soil data, and establish grazing exclosures.
2)Collect vegetation and soil monitoring data at each site 1 to 2 times per grazing period
3)Hold a grazing tour at one site with the researchers and producer.
4)Collect financial and production records to begin economic analysis.
5)Hold an annual meeting to go over data collected and plan tours for next year.
Accomplishments/Milestones
1)Site establishment
In May 2012, we established the sites for vegetation and soil sampling at the 9 producer sites (Figure 1; Gary, Hayti, Chamberlain, Lowry, Eureka, Reliance, Belvidere, Quinn, and New Underwood). At each site we established several grazing exclosures to sample soil and get estimates of annual forage production. The baseline soil organic matter (SOM), nitrogen, carbon, and carbon:nitrogen was determined form soil sampling the top 0-3 inches. The results from these are shown in Table 1.
2) Vegetation data collection
Vegetation was sampled along 50-m transects and estimating foliar cover of grass, native forbs, introduced forbs, and shrubs using a 0.25 m2 quadrat every 5-m (Figure 2). We also estimated bare ground, old litter, and newly trampled litter. Vegetation height and soil electroconductivity was measured every 2 m2. Dung density also was collected along the same transect every 5 m using a 1 m2 quadrat (Figure 2). Four 0.25 m2 samples were clipped to estimate standing biomass and litter.
Producers conducted mob grazing on their ranches. Stocking density ranged from 20,000 to 1,000,000 lbs of beef per acre with cattle rotated once per day up to nine times per day. In 2012, three sites had rotational grazed pastures (stocking densities <5000 lbs of beef per acre) that were used for comparison to the mob grazed sites. In 2012, South Dakota experienced drought conditions that led to less than optimal growing conditions and as a result low forage production (Figure 3).
One of the primary reasons for mob grazing is to trample uneaten grass biomass to build soil organic matter. This was measured through contributions of new litter. New litter contributions by trampling are shown in Figure 4.
The Hayti site was a big bluestem pasture (tall warm-season grass) and the New Underwood site was predominately crested wheatgrass with some alfalfa. On average the mob grazed sites added 15% new litter cover compared with 6% new litter under traditionally managed rotational grazing. Due to drought these amounts are much less than what we would have expected under a normal precipitation year.
Another important aspect of mob grazing is the even distribution of manure, thus enhancing the nutrient cycling. Figure 5 shows the dung density at each location. Mob grazed sites had an average of 0.45 dung pats per m2 compared with just 0.2 dung pats per m2 at the traditional rotationally grazed sites.
Grass removed by grazing is a measure of grazing efficiency. At the Eureka site mob grazing resulted in about a 50% disappearance of the grass cover compared with 40% in the rotation (Figure 6). At the Reliance site mob grazing resulted in a 75% disappearance of grass cover compared with 45% in the rotation (Figure 6).
3) Grazing Tour
In July 2012, we had a tour at the Chamberlain site hosted by Charlie Totton. We observed his cattle and mob grazing under 107oF temperature that day. We discussed the benefits he was having and observed that the soil temperature (2 inch depth) was 50oF less than his neighbor who practiced season-long grazing (Figure 7).
4) Financial and production records
Visits were made to six of the nine cooperating producers in August 2012 to interview producers in order to develop a better understanding of the nature of the existing grazing sites to begin the development of an economic model to assess profitability of mob grazing systems. Producers were interviewed in regards to infrastructure and management changes that had to be made to initiate the practice, management changes that have evolved within operations over several years of mob grazing, and perceived benefits and downfalls to the systems.
Each of the sites enrolled in the project are dynamic, and each have been established to accomplish a variety of different management goals for beef production. Some producers graze cow/calf pairs after the cows are bred during the summer months, whereas one producer uses his mob grazing system for breeding. Some use mob grazing for fall grazing of crop residue or cover crops with cows, and one producer raises grass finished beef in his mob grazing system. For each of these management practices, profitability is defined quite differently. For example, pounds of gain are of importance in the grass finishing system, whereas conception rates are important when the system is used for breeding. Accordingly, there is not one single animal performance output that can be applied for mob grazing relative to profitability. In interviewing producers, it was evident that the most measurable common denominator in the establishment of a mob-grazing system within an existing production operation was an extension in the number of grazing days or the potential to increase stocking density. This will be incorporated as a measure of profitability in the economic analysis of the project.
Input costs: The two largest costs associated with building infrastructure for mob grazing systems are developing water and fencing.
Water: Within the project the initial set-up and maintenance for water are diverse across producer operations. One producer had large initial overhead costs associated with having to drill a well and put water lines in to feed the mob grazing system, whereas some producers were able to develop a mob grazing system out of an existing rotational grazing system which already had water in place. Producers indicated that logistics with water was one of the most challenging aspects of the practice and have not yet found a “perfect watering system”. After learning this information, we will work to incorporate water infrastructure into a budget to include estimates for installing water pipe and purchase of water tanks.
Fencing: Aside from water, fencing is the other largest cost incurred in the establishment of a system. One important aspect of fencing the system is the establishment of a good perimeter fence that can provide flexibility for cross-fencing. Again, the fencing set-up across the producer sites enrolled is diverse. Some producers made use of an existing perimeter fence and some established a new perimeter fence; whereas some only used hotwire for the entire system. Fencing costs will be included in the development of a budget for mob grazing by establishing costs for both a permanent perimeter fence as well as prices for cross-fencing with hot wire.
Labor: The intense and frequent moving of cattle that is part of the mob-grazing practice obviously creates an increased demand for labor. However, producers within our project do not seem to view increased labor as a burden to daily operations. Once the system is set-up and cattle become accustom to the practice, they are typically ready to be moved, which expedites the process. Most producers find value in the more intense grazing management as a means to more frequently monitor health and well-being of cattle. Of course the labor requirement depends directly on the dynamics and intensity of the system as some systems are designed for more frequent moving than others.
Establishment of the system (why did producers choose to implement mob grazing): Producers engaged in mob-grazing tend to be more “holistic” in terms of their management styles and each have become involved in the practice for a variety of reasons. This project is working to validate many of the claims that are made in popular press relative to the ecological benefits of the practice. In interviewing the producers in this project, many expressed weed control as one of the greatest benefits of the practice in addition to the capacity to extend grazing days, improved forage quality, and the ability to stockpile forage for later grazing. This information, along with findings from data collected will be used to validate these claims. For example, if we are able to validate that invasive species are reduced by mob grazing, then this would reflect in a reduction of herbicide application as compared to a rotational or continuous grazing system.
Forages grazed: The variety of forages grazed by producers engaged in mob-grazing in this project is diverse. Most producers incorporate grasses into their system, some use the practice for grazing cover crops whereas some use mob-grazing to graze crop residue to help prepare the field for no-till drilling of a subsequent crop. The economic model developed should evaluate both the beneficial aspects of additional grazing days (and the capacity to increase stocking rate), in addition to the merits of the grazing system from an agronomic standpoint.
Animal health: One of the biggest challenges observed in the late summer visit to these operations was fly control with within the concentrated grazing system. Some producers were making use of fly tags, pour-on and fly spray; this is one aspect of the practice should be more closely monitored.
Remaining work: We are currently working toward the development of an economic model to incorporate each of the aforementioned aspects, together with findings from field data to help determine overall profitability of a mob grazing system vs. other grazing management practices.
5) Annual producer meeting
On December 5, 2012 we held an annual meeting in Chamberlain. We presented an overview of what we had accomplished and provided a 3-ring binder of the data that we collected for each producer. We discussed tours for the summer of 2013 and data collection. It was decided that we would try to host 2 tours and produce a virtual tour at some of the other sites. The virtual tours will be a video with an interview style. We will hire SDSU communications to produce the videos.
Impacts and Contributions/Outcomes
We have completed the first year of the mob grazing study. So far we have gained some insight into the mechanisms governing the trampling effect and adding litter to cover bare ground in relation to stocking density, plant height, and location (influence of local plant-soil-climate factors). Mob grazing did increase the distribution of cattle manure. It remains to be seen how the soil health will change, ultimately affecting plant productivity. The financial and production assessment is incomplete, but we do know that there are some grazing efficiencies that extend the number of animal unit days per pasture under this system compared with less intensive rotations.