Originally written by James Doyle, former SDSU Extension Natural Resource Management Field Specialist.
Broadacre spraying of pastures is intended to reduce undesirable plants and increase grasses for livestock. This practice often results in unintended consequences including damage and reduction of native forbs and reduced profitability. One approach to managing perceived “weedy” plants that can offset those negative outcomes is incorporating different species of livestock into a grazing operation.
All species of livestock have different dietary preferences, and producers can harness this to help manage their plant communities in an ecologically and economically sustainable manner. Small ruminants, in particular sheep and goats, are the most common livestock species that are added alongside a cattle enterprise.
All species of livestock have different preferences when it comes to selecting the species of plants they consume, as demonstrated in Figure 2. Generally speaking, cattle diets are dominated by grass, a moderate forb component, and very little browse (or woody plants); goats are on the opposite end of the spectrum, with a strong preference for browse, followed by forbs and a minor grass component; sheep are intermediate, with a selection for forbs, grass, and a moderate browse component. By incorporating additional livestock species, producers can manage previously undesirable plants with a positive outcome. Broadcast spraying can have very damaging effects on native forbs, and rarely results in lasting eradication of undesirable plants. Additionally, a pasture spray program can be very expensive, with little evidence to suggest that the expense is recaptured in increased grass production and pounds of beef harvested. In contrast, sheep or goats can effectively utilize plants that cattle avoid. Harvesting these additional plant species with a different species of livestock can effectively increase the pounds of livestock produced per acre, without damaging the plant community. This can provide a level of management of undesirable species in conjunction with increased economic returns. In fact, this may lead you to question whether some of those “weeds” might actually be good to have around!
As with any livestock, it is important to not overstock the pasture or range when bringing in a new species. First and foremost, the stocking rate of the livestock needs to be in line with the production of the land. A general rule of thumb when adding sheep to a cattle enterprise is that one ewe can be run alongside each cow without negatively affecting the pasture health or forage availability for cattle. For instance, a 100 cow operation could add 100 ewes to their pastures, without reducing capacity for the cows, or damaging the pastures; this demonstrates how it is possible to harness the differences in dietary preferences to increase the overall output of your pastures. With goats, this ratio may be even higher because of the greater difference between the diet of goats and cattle. This 1:1 ratio is just a rough starting point. Producers should inventory their pastures to have an idea of the different plant species present. Pastures with very high forb or shrub content may be able to support more sheep, and conversely pastures that are almost entirely grass may not be able to run as many sheep alongside the cattle. As with any new enterprise, the best approach is to start conservatively, observe the animal behavior and effects on the pasture, and then adjust accordingly.
Bringing a new species of livestock on to an operation comes with plenty of challenges, as well as opportunities that should be considered carefully. One of the primary challenges with sheep or goats is fencing, as most cattle fences will not contain them reliably. Woven wire is an ideal fence for the small ruminants, but additional hot wires added to an existing fence can be a relatively inexpensive way to improve a fence. Additionally, improvements in portable electric fence have made it increasingly easier to manage sheep and goats in pastures that don’t have permanent fencing in place. Additionally, portable fencing can enable managers to more effectively target grazing on certain species or areas. Lambing or kidding can also demand a significant amount of labor that should be considered. On the other hand, lambing/kidding results in an additional crop of market livestock to sell that can improve the overall returns, as well as smooth cash flow by providing income at different times of the year and diversifying income across different markets. Of course, going out and purchasing a flock of sheep or goats is not the only way to realize the benefits of their presence. This can provide an excellent opportunity for land managers to partner with sheep owners to provide access to pasture while receiving a rental income for the grazing, the ecological benefits of a new species, and less of the risk/hassle associated with developing a new enterprise. The recently launched South Dakota Grazing Exchange can help connect livestock owners and land managers. Finally, it is important to note that landowners are still obligated to control noxious weeds on their property, which may still require targeted mowing/clipping or spot spraying. As with anything, multi species grazing should be considered as another tool managers can utilize, but not a silver bullet for everything.