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Grazing Basics. Central Wisconsin Grazing Meetings March 2008. Craig Saxe UW-Extension, Juneau Co. 211 Hickory Street Mauston WI 53948 (608) 847-9329 craig.saxe@ces.uwex.edu. We’ll be covering. What is rotational grazing Why use rotational grazing Understanding plant growth
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Grazing Basics Central Wisconsin Grazing Meetings March 2008 Craig Saxe UW-Extension, Juneau Co. 211 Hickory Street Mauston WI 53948 (608) 847-9329 craig.saxe@ces.uwex.edu
We’ll be covering • What is rotational grazing • Why use rotational grazing • Understanding plant growth • Setting up a grazing system • Fencing, watering and frost seeding • Grazing tips
Fundamentals of successful grazing management • Meet the nutritional needs of the livestock from standing pasture • Optimize pasture yield, quality, and persistence • Maintain or enhance the natural resource base • Integrate appropriate technology and knowledge into a practical system
Size of animal Number of animals Daily intake Forage availability Desired rotation length Setting up a Rotation The example to follow was created by Laura Paine
How much forage is out there? Rule of thumb: Figure about 400 pounds dry matter per acre per inch of cool season pasture. L. Paine
How much do my animals need? Rule of thumb: Figure 2.5 to 4% of body weight dry matter per animal per day. L. Paine
How big should my paddocks be? • Paddock size equals: Number of head x Daily Intake (3% ) x No. of Days Available Forage/Ac./Rotation L. Paine
What does a sheep eat in a day? • One ewe/lamb pair weighs about 200 lb • Daily forage need/pair = 3% of body weight = 200 x 0.03 = 6 lb of dry matter/day L. Paine
What does your flock eat in a day? • One ewe/lamb pair eats 6 lb/day • 20 pairs eat 120 lb/day • 50 pairs eat 300 lb/day • 100 pairs eat 600 lb/day L. Paine
When should I graze and how much forage is out there? • Graze when pasture is 8 to 10 inches high (depending on species). • Take half-leave half rule: graze down to 4 or 5 inches. • At 400 lb/inch, you have 1600 to 2000 lb/acre to work with. L. Paine
How long should I leave the flock on one paddock? • One to three days. • Above 3 days, you’re regrazing grass that you grazed the first day. • The shorter the rotation, the better quality and forage utilization you’ll have. L. Paine
Putting it all together • Flock of 100 ewes with lambs. • 3-day rotation. • Need 600 lb forage/day. • 600 lb x 3 days = 1800 lb/paddock. L. Paine
Putting it all together • Ready to graze pasture = 1600 lb forage/acre available to use. • Acreage needed to last 3 days = 1800/1600 = 1.13 acres. • Just over one acre/paddock. L. Paine
Determine Number of Paddocks • 30 days 3 day rotation + 1 = 11 paddocks • 11 paddocks x 1.13 acres/paddock = 12.43 acres L. Paine
Another Example: Stocker Cattle • 100 stockers or heifers, 1 day rotation, 2000 lb/a available forage • Beginning weight = 400 lb; ending weight = 800 lb; • average weight = 600 lb. • Paddock size equals: (100 x (600 x 0.03) x 1) 2000 = (100 x (18) x 1) 2000 = 1800 x 1 2000 = 1800 2000 = *0.9 acres* L. Paine
Determine Number of Paddocks • 30 days 1 day rotation + 1 = 31 paddocks • 31 paddocks x 1 acre/paddock = 31 acres L. Paine
100 animals 1 day rotation 30 day cycle 1 acre/paddock 31 paddocks Stockers or Heifers L. Paine
The Rest Period • Should vary according to plant growth • In general, must increase as growth rate slows • Relates closely to seasonal forage growth • Need to rotate between paddocks every 3-6 days (or less)
Relationship of rest period to pasture mass during periods of rapid vs. slow growth Lbs. DM / acre Optimum Rest Period 0 5 10 15 20 25 Period of fast plant growth (days) 0 10 20 30 40 50 Period of slow plant growth (days)
Maximizing Intake • Three controlling factors • Grazing time • Biting rate • Bite size Jim Gerrish, Dodge County Grazing Conference, 2002
Of the three controlling factors, bite size is all we can control! Jim Gerrish, Dodge County Grazing Conference, 2002
Change in daily intake from day 1 to day 7 of week grazing period 1 2 3 4 5 6 7 Jim Gerrish, Dodge County Grazing Conference, 2002
Which will cause more overgrazing? The stocking rate of both paddocks is identical: 100 Animal Days per Acre. The effect on the paddocks will be much different.
Stocking Rate (animals/acre) • Can use formulas for actual numbers • Thumb rule; 1000 pound animal per 2-4 acres • Intensive Rotational Grazing = 1000 pound beef animal to 1-1.5 acres • Traditional “Under-managed” pastures = 1000 pound animal to 5-10 acres
Radial pasture configuration - before NRCS, Bozeman, MT
Radial pasture configuration – after NRCS, Bozeman, MT
Another pasture configuration - before Explanation Bare Buildings Fences Lawn Property Streams Trees Water Weeds
Another pasture configuration - after Explanation Bare Buildings Fences Lawn Property Streams Trees Water Weeds