|We're here to help Ewe! Unlike cattle, which won't eat leafy spurge and generaly avoid dence infestations, sheep will readily graze the weed once an aversion to the taste is overcome. Leafy spurge, in fact is quite nutritious: It has good crude protein values and is highly digestible, and it provides excellent forage for lambs and lactating ewes. Sheep generally show good weight gains after grazing spurge.|
|Lefy Spurge Nutitional Values|
|Growth Stage||% Crude Protein||% Phosphorous||% Dry Matter Digestibility|
Cattle, sheep and goats have different dietary preferences and grazing behaviors. Cattle prefer grasses, sheep prefer forbs, and goats are browsers. Multispecies grazing exploits the complementary aspects of these dietary differences.
Cattle wonít eat leafy spurge, and generally avoid heavily infested patches. Infested land thus loses some of its economic potential by reducing the production of desirable grasses, leafy spurge ultimately limits the number of cattle the range can support.
Sheep and goats, however, will readily graze leafy spurge, thus converting a noxious weed into an economic gain rather than an added expense for control. The weed, in fact, has high crude protein and feed values, and provides excellent forage for sheep (especially lactating ewes) and goats.
Grazing by sheep or goats stresses leafy spurge, taxes its root system, reduces seed production, and increases its vulnerability to other control tools (such as biological control or herbicides). It can be used to prevent the spread and reduce the density of leafy spurge infestations, and will ultimately provide a long-term management tool that reduces the weed to tolerable levels.
Instead of investing precious time and money to manage the weed, ranchers can integrate sheep or goat grazing into existing operations to control leafy spurge while improving range health and potentially generating an economic return.
|Notice Any Difference?|
This fenceline contrast provides an excellent example of the control that can potentially be achieved with multi-species grazing. Spurge densities on the left are inhibiting the production of desirable grasses and drastically reducing the pastureís value to a cattle producer. On the right side of the fence, sheep are being used to reduce, then maintain, a significant reduction in leafy spurge densities, resulting in a pasture that can once again be utilized for cattle grazing.
Multi-species grazing offers many benefits when compared to singlespecies grazing. Some of these benefits are quite significant:
o Control: When incorporated as a longterm management tool, multispecies grazing can reduce leafy spurge densities by 80-90% after three to five years of grazing.
o Sustainability: Multi-species grazing can be used year after year, and can be used in inaccessible or environmentally sensitive areas where other control tools wonít work or canít be used. Riparian areas provide a good example. Herbicide use in such areas is often restricted by environmental regulation, and biological control can be hampered by high water tables and sandy soils. In these situations, grazing provides a viable alternative.
o Range utilization: Multi-species grazing improves range efficiency by using different species to graze different parts of the range i.e., it uses sheep to utilize forage that cattle will not be use. With proper management and monitoring, this improvement in range efficiency can contribute to a healthier, more productive range.Well-managed multi-species grazing programs often result in the ability to increase cattle numbers, as shown by studies at the NDSU-Hettinger Research Extension Center and other research facilities.
o Livestock performance: Combining cattle with sheep or goats generally results in increased performance for one or both species. In widely dispersed and replicated studies in the U.S. and Canada, cattle grazed with sheep had weight gains as much as 21 percent more than cattle grazed alone. The same studies show that sheep grazed with cattle had gains of 12-36 percent more than sheep grazed alone.
Improved range health
Increased forage production
Improved forage utilization
Enhanced livestock performance
Leafy spurge control
Control of other noxious weeds
Works well with other tools
o Flexibility: Multi-species grazing systems offer flexibility by allowing range managers to adjust cattle and sheep numbers depending on the desired outcome. If spurge control is the primary objective, for example, ranchers can "turn up the heat" by increasing sheep numbers for a certain period of time.
o Integration: Multi-species grazing is an excellent tool to combine with other management tools, such as biological control or herbicides. TEAM Leafy Spurge demonstration sites using combinations of multi- species grazing with biological control and herbicides have produced promising results.
o Other weeds: Leafy spurge is not the only weed sheep and goats will consume. Other weeds include spotted knapweed, ragwort, larkspur, fringed sage, wormwood, and some thistles and mustards.
|Grazing + Biological Control|
This fenceline contrast provides examples of several important leafy spurge management concepts. An aggressive, long-term herbicidebased approach prevented spurge from becoming a problem on the right side of the fence. This approach provided good leafy spurge control, but was relatively expensive and reduced ecological diversity. The lack of persistent management efforts on the left side of the fence resulted in dense, widespread leafy spurge infestations that ultimately reduced the production of desirable grasses. Flea beetles were released in the mid-1990s, but significant control was not achieved until a multi-species grazing program was implemented in 1998. The results since integrating grazing and biological control have been quite impressive. The lesson is simple: The sooner you start an aggressive, integrated leafy spurge management program, the sooner youíll benefit.
First off, there are no management tools that will completely eradicate leafy spurge itís just not that easy or simple. Different tools offer different types of benefits, but there are no "silver bullets" that will work every time in every situation.
Multi-species grazing, however, can be an effective part of the solution. A properly managed multi-species grazing program that is in harmony with the environment will slow and eventually prevent the weedís spread, enabling native grasses to reestablish, proliferate and ultimately contribute to increased carrying capacity.
And, much the same as other management tools, multi-species grazing is not an overnight solution. It takes a commitment and time.
Hereís a brief chronology of what can be expected after implementing a multispecies grazing program:
Year One Sheep will typically not be an aggressive grazer of leafy spurge, especially early in the grazing season. At some point, sheep will overcome their initial aversion to leafy spurge and begin consuming larger quantities of the plant. Defoliation should be evident late in theseason.
Year Two Sheep will be more aggressive, and grazing of leaves, shoots and whole stems should be evident by seasonís end. This will stimulate increased leafy spurge growth, and the emergence of new plants early in the season. However, this new growth will likely be removed by grazing sheep as the season progresses.
Year Three Leafy spurge densities should be noticeably reduced from original pre-sheep levels. Cattle will begin grazing in areas previously dominated by dense spurge infestations.
Year Four The plant and its system has now been stressed to the extensive reductions. Leafy spurge densities should be much lower, and grasses will begin re-establishing once dominated by leafy spurge.
Year Five and Beyond Multi-grazing programs need to be monitored and maintained to prevent leafy from re-establishing. At this point, multispecies grazing can be considered maintenance program.
Introduction Table of Contents Economics