Grazing Management For Healthy Watersheds

1. Grazing Management For Healthy Watersheds Dr. M. Karl Wood Director Water Resources Research Institute New Mexico State University

2. What is a healthy watershed? Desired Functioning Condition? What are the Goals? Are the Goals Obtainable and Sustainable?

3. Watershed Goal? Resource Exploitation Sustainable Use Resource Protection

4. Watershed Goal? Exploitation Sustainable Protection Use The extremes result in attitudes of supremacy From: Thompson, P.B. 1995. The Spirit of the Soil - Agriculture and Environmental Ethics. Routledge Publ. New York, New York

5. New Mexico Historical Perspective Wild Ungulates native to New Mexico Cous deer Whitetail deer Mule deer Pronghorn Bison Rocky Mountain bighorn Desert bighorn Javelina Elk

6. Domestic and Wild Ungulates Introduced in last 500 years Cattle Horses Barbary sheep Swine Oryx Goats Ibex Sheep Burros

7. Grazing Effects on Plants

8. Land Management Practice Animal Grazing, Trampling, and Burrowing Plant and Rock Cover Plant Volume Soil Surface Configuration Soil Surface Roughness Soil Moisture Evaporative Loss Soil Organic Matter Content Soil Particle Sizes Soil Bulk Density and Porosity Soil Structure Runoff and Infiltration

9. Grazing Effects on Plants 1. Grazing reduces plant cover and volume 2. Plants species respond differently to grazing Little Great Stimulation Resistance Resistance Response Black grama Blue grama Antelope bitterbrush

10. Grazing Effects on Plants 2. Plants species respond differently to grazing continued… Moderate to No Grazing Bunchgrass Heavy Grazing Sodgrass Blue grama Blue grama

11. Reduced Plant Cover and Plant Volume Effects the Watershed 1. Decreased interception and transpiration • Decreased organic matter additions to soil, which • affect soil structure and porosity 3. Decreasedwater infiltration into soil surface 4. Increased runoff and erosion • 5. Increased runoff and erosion lead to loss of sustainability after about 50% utilization of present year’s growth

12. Grazing Effects on Plants Continued… Grazing can retard or stop invasion of salt cedar Observed on: 1. Capitan Creek on the Pecos River 2.Middle Fork of the Gila River 3. Redstone Allotment of the Gila River

13. Trampling or Hoof Action Effects on Plants • Trampling reduces plant cover and volume. 2. Plant cover and volume reductions may: a. Decrease Interception and Transpiration b. Damage or kill the plants c. Stimulate plant growth

14. Trampling or Hoof Action Effects on Soils

15. Trampling Effects on Soils Soil Surface Runoff and Roughness Erosion Wet Soil Dry Soil Increases Decreases Decreases Increases Southwestern soils are usually dry!

16. Trampling Effects on Soil Configuration Runoff and Trails Erosion Up & Down Slopes Across Slopes Increases Decreases

17. Trampling Effects on Soil Bulk Density and Porosity Bulk DensityPorosity Water Holding Runoff and Capacity Erosion Increases Decreases Increases Increases Bulk Density increases are usually mitigated with cold-weather freeze-and-thaw conditions.

18. Trampling Effects on Soils When ungulates are removed from watersheds, pocket gopher populations often increase, even exponentially. Gopher mounds may add up to 5 tons/acre/yr of sediment into streams!

19. Trampling Effects on Soils Gopher tunnels often lead to piping and eventually a side gully! A benefit of trampling is control of pocket gophers!

20. Animal Wastes and Nutrient Cycling Wind Soil Runoff and Erosion

21. Animal Wastes and Water Pollution Only that dung deposited on bare ground connected to a runoff system is expected to be eroded from a watershed. Fisheries in high fertility watersheds won’t benefit much from dung and urine additions but may suffer from over-enrichment. Fisheries in watersheds of low fertility may benefit from accelerated erosion and elevated nutrient levels

22. Livestock and Wild Ungulate Management Strategies Fences It is easy to fence out livestock It is difficult to fence out wildlife Total number of ungulates may not change from fencing out livestock

23. Livestock and Wild Ungulate Management Strategies Fences and exclosures may be problematic because they: Often result in unused forage Create problems with animal movement Have annual maintenance hassles Are expensive Lead to aesthetic considerations

24. Livestock and Wild Ungulate Management Strategies Stocking Rates Extreme 100% Utilization - Rarely sustainable Heavy 75 “ - “ “ Moderate 50 “ - Usually sustainable Light 25 “ - “ “ Exclusion 0 “ - “ “

25. Livestock and Wild Ungulate Management Strategies

26. Livestock and Wild Ungulate Management Strategies Grazing systems

27. Grazing Systems – Example from Texas Rolling Plains Stocking Infiltration Sediment System Rate Rate Production cm/hr kg/ha Exclosure None Deferred-Rotation Moderate Continuous Moderate Short Duration Moderate Continuous Heavy 11 b 14 b 28 ab 40 ab 114 a 15.2 a 13.9 ab 11.4 bc 8.2 c 8.1 c Wood and Blackburn. 1981. J Range Manage. 34:228-231; 331-335

28. Grazing Systems – Example from Fort Stanton, New Mexico Stocking Infiltration Sediment System Rate Rate Production cm/hr kg/ha Exclosure None Continuous Moderate Short Duration Heavy after resting Short Duration Heavy after grazing Continuous Heavy 65 b 307 a 221 a 565 a 334 a 7.4 a 4.9 b 3.9 c 2.3 d 2.6 d Weltz and Wood. 1986. JRM 39:365-368; J Soil & Water Cons. 41:262-266.

29. Grazing Systems – Example near Fort Sumner, New Mexico Stocking Infiltration Sediment System Rate Rate Production cm/hr kg/ha Exclosure None Continuous Moderate Short Duration Heavy after resting Short Duration Heavy after grazing 6.3 ab 20 c 80 b 25 c 268 a 5.5 b 7.0 a 3.8 c Weltz and Wood. 1986. JRM 39:365-368; J Soil & Water Cons. 41: 262-266.

30. Livestock and Wild Ungulate Management Strategies Range Improvements Plant Control Biological Burning Herbicides Mechanical

31. Livestock and Wild Ungulate Management Strategies Range Improvements Plant Enhancements Seeding Fertilizing Waterspreading

32. Livestock and Wild Ungulate Management Strategies Monitoring Explore Observe Measure Keep Records Evaluate

33. Four noteworthy points can be made regarding the question: Can we graze watersheds? Conclusions 1stYes, we can graze these areas! 2ndWe should be able to increase forage produced without damaging other uses! 3rdWe don’t know yet how to do this in all areas! 4thIf we don’t get our management act together, the public won’t let us graze watersheds because of high resource value and potential for damage from improper grazing!

34. A Good Quote “If the prime objective is wood products, we may continue to overgraze, letting in the woodland and sacrificing watershed values. If on the other hand the prime objective is watersheds, we should restore the grass, which all the evidence indicates is a better watershed cover than either brush or woodland.” Aldo Leopold

35. God Bless America!