Managing Grazing for Sustainable Pastures

1. Managing Grazing for Sustainable Pastures Developed by: Wendy Williams, Natural Resources Conservation Service, Montana Holly George, University of California Extension Service NRCS, Bozeman, Mont.

2. We’ll be covering • Benefits of implementing grazing management • Steps to effective grazing management • Estimating carrying capacity • Monitoring your land by making footprints • Grazing systems and pasture configurations • Grazing tips

3. Why manage grazing? • Keep plants healthy and productive • Increase forage production and saves money • Increase grazing capacity • Improve use of forage supply throughout the year • Help control weeds USDA NRCS

4. Why manage grazing? • Allows for maximum vigor of key species • Allows seed production by key species • Allows seedling establishment of key species • Meets other management goals (fire hazard, birding, housing beneficial insects, etc.) www.forages.orst.edu

5. Why manage grazing? • Reduces erosion • Improves water quality • Improves range or pasture condition NRCS, Bozeman, Mont. T

6. Why manage grazing? • Allows for flexibility • Enhances wildlife habitat • Maximizes efficiency of your time and resources elib.cs.berkeley.edu

7. What crop are you managing? Your pasture plants, of course! www.farmphoto.com

8. Key points to remember about pasture plants: • The leaves manufacture carbohydrates for the plant. You must reserve some leaf volume for this purpose. • To ensure regrowth, you must preserve the growing points on your plants.

9. Deitz, NRCS

10. Deitz, NRCS

11. Steps to effective grazing management: • Graze to the desired stubble height. • Don’t forget to preserve growing points. • Allow adequate rest periods for grass regrowth. • Don’t regraze a pasture until your key species has reached the desired height. • In an irrigated pasture, don’t let seed heads form.

12. How many animals can I graze? ACES

13. Matching animals to available forage • This is not determined by local zoning! • Amount of forage varies by season, climate, length of growing season, soil type, water availability, etc. • Animal needs vary by age, condition, amount of exercise, pregnancy, etc.

14. No matter how many animals… some things are the same You need to know: • CARRYING CAPACITY, or the number of animals a pasture can accommodate without overgrazing • STOCKING RATE, or the amount of forage stock are going to eat UNCE, Reno, Nev.

15. Jan Feb Dec Nov Mar April Oct Sept May August June July We can predict when grass will grow, but not necessarily how much

16. What do animals need and when? Birth Before Birth Peak Lactation Last 1/3 Breeding Lactation Wean Late Lactation

17. Do the nutritional needs of the animal match the forage availability?

18. Methods for estimating carrying capacity • Pasture sticks and other physical methods • Animal Unit Months • Animal Days per Acre UCCE

19. Determine carrying capacity • Remember that grazing animals only need to eat about 2.5 to 3% of their body weight • An 1,100 pound horse will eat 27.5 pounds of air-dry forage (hay) per day, or 825 pounds per month (27.5 x 30)

20. Determine carrying capacity • Horses trample or damage 25% of their forage in a pasture, so add another 25% when feeding from a pasture – this brings the total requirement closer to 1,000 pounds per month

21. Pasture sticks

22. AUM – Animal Unit Month • Animal Unit: the forage consumption of one 1,000-pound cow plus calf • Animal Unit Month: the amount of forage required for one animal unit for one month (AUM) • All other animals are compared to one 1,000-pound cow plus calf

23. AUM equivalents

24. 1 AUM equals: 1 cow and calf OR: • 2 weaned calves • 5 sheep • 5 goats • 3 llamas • 5 deer • 2 elk • Etc. All require 1,000 pounds per month of air-dry feed

25. ADA: Animal Days per Acre • A formula for determining how many animals can graze a specific pasture for a given period of time www.farmphoto.com

26. Some ways to use ADA: • To assess pasture productivity • To determine if a pasture can supply enough forage for a future planned grazing period • To determine the area required to supply daily forage requirements for one animal • To set stocking rates • But…it does NOT tell you anything about the nutritional content of the forage!

27. Estimating carrying capacity in ADA 10 yards Pace off an area of pasture that one animal would need for grazing for one day as the sole source of forage 10 yards

28. Calculate stock days per acre • Multiply the length by the width • Calculate square yards per acre needed per animal per day • Divide 4,840 square yards per acre by square yards needed per animal per day • This gives Stock Days per Acre (SDA)

29. Stock days per pasture • Multiply SDA by the number of acres in the pasture • The total represents the total number of stocking days in the pasture www.farmphoto.com

30. How many days can you allow livestock to graze? • Divide stock days by the number of horses (or other livestock) • This tells you how many days you can graze the pasture with that number of animals NRCS, Bozeman, Mont.

31. 25 yards Let’s try an example • You have 5 acres of pasture and four horses • Your experimental time period is one day • Area width and length are both 25 yards

32. Step 1: Calculate stock days per acre • Calculate the area by multiplying length x width: 25 yards x 25 yards = 625 square yards • Divide 4,840 square yards per acre by 625 square yards per animal day 4,840 square yards/625 square yards = 7.7 stock days per acre (SDA)

33. Step 2: Calculate total stock days per pasture • Multiply the stock days per acre times the total number of acres in the pasture 7.7 SDA x 5 acres = 38 stock days

34. Step 3: Calculate the number of grazing days for the pasture • Divide the number of stock days by the number of horses 38 SD / 4 horses = 9.6 days You can graze the five-acre pasture with four horses for 9.6 days

35. Improving carrying capacity • Manage grazing • Create and use exercise areas and paddocks • Control weeds • Improve irrigation • Consider need for reseeding or renovation

36. How do you know if your estimated grazing length is correct? Walk your land and look! UNCE, Reno, Nev.

37. Overgrazing occurs two ways: • Leaving stock in a pasture too long OR • Bringing them back too soon NRCS, Bozeman, Mont.

38. Stocking rate vs. stock density • The stocking rate of both paddocks is identical: 100 animal days per acre • However, the stock density is much greater in the pasture on the right, so the effect will be much different!

39. How do you know when to graze, and when to rest?

40. Length of rest period • Depends upon: • Period in the growing season • Availability of irrigation water • Amount of active leaf area remaining following the grazing period • Cool-season grasses recover more quickly in spring and autumn

41. Monitoring • Use observations and common sense • If there isn't enough feed in your pasture, you are either overstocked or not allowing enough rest, regardless of what the calculations said www.agry.purdue.edu

42. Monitoring grass height www.agry.purdue.edu UNCE, Reno, Nev.

43. Make footprints to manage well • Get out on the ground and look at what is happening • Your footprints and observations of how pastures and stock look are critical to making the necessary adjustments UNCE, Reno, Nev.

44. Three important questions • Look BEHIND: What rest period do my pastures need? • Look AHEAD: Has the paddock had enough rest? • Look WHERE the STOCK ARE: Is the stocking rate correct?

45. Look BEHIND: Before making decisions about grazing periods, know how much rest is needed: • Make footprints in pastures that stock have already grazed to evaluate regrowth • If grass has grown a couple of inches in 1 to 2 weeks, plan relatively short rest periods (30 to 45 days) • If not much regrowth has occurred in 1 to 2 weeks, plan for longer rest (60 to 120 days)

46. Look AHEAD: Has the pasture had enough rest? • Make footprints in the pasture. Make sure it is ready! • If the production is low, don’t graze it yet • If you graze the pasture before it’s ready, stock will find less and less grass waiting for them each move www.farmphoto.com

47. Look WHERE THE STOCK ARE: Is the stocking rate correct? • Make footprints in the paddock currently being grazed to observe severity of use • If use is too severe (not enough stubble height), the pasture is overstocked • Either reduce stocking level OR lengthen the rest period www.farmphoto.com

48. What did your monitoring tell you? NRCS, Bozman, Mont.

49. J. Mohler, Mont.

50. Good cover NRCS, Bozeman, Mont.