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Profitable Pastures

A guide to grass, grazing, and good management

Managing Forages

A sound grazing plan adjusts the length of grazing and resting periods to balance the needs of livestock and the plants they eat, and usually includes rotational grazing of two or more pastures.

Rotational grazing systems promote plant and root growth, reduce soil erosion, provide wildlife habitat and protect water quality.

In addition, rotational grazing systems are designed to promote optimum forage utilization, extend the growing season and increase carrying capacity and profit potential. 

The length of rest period for a desired plant species varies throughout the season. When growing conditions are good, the rest period may be as little as 15 to 20 days. Later in the season, 45 to 50 days may be required to ensure adequate rest.

Rest periods speed plant growth and can be used to help establish and maintain legumes in the forage stand. During periods of fast growth, rests should be shorter to keep plants from going to seed. Longer rests periods are needed when pasture growth slows.

Legumes need at least a 30 day rest during the growing season to allow for regrowth and reseeding.

In a 2 to 4 paddock system, livestock could be moved every 7 to 14 days. However, with more intensive systems, plan for rest and regrowth periods of 25 to 35 days. This would require 5 to 12 paddocks and moving livestock every 2 to 8 days depending on stocking density and plant growth.

Try to move livestock according to plant growth and not just calendar days.

Forage Guidelines
Forage Full Seeding Rate, #/acre Begin grazing at Graze no closer than Cut for hat at Allow regrowth to this height before killing frost
Cool Season*
Kentucky bluegrass 5-10 4-6" 2" Not recommended 4"
Orchardgrass 8-12 6-10" 4" Boot to early head 6"
Reed canarygrass 8-12 8-10" 4" Early boot 6"
Smooth bromegrass 10-16 6-12" 4" Medium to full head 6"
Tall fescue 8-15 6-10" 4" Boot to early head 6"
Timothy 4-8 6-10" 3" Early head 5"
Warm Season**
Switchgrass 5-7 16-20" 6" Early head 6"
Indiangrass 10-12 12-16" 6" Boot 6"
Big bluestem 10-12 10-16" 6" Boot 6"
Legumes*
Birdsfoot trefoil 5-8 6-10" 4" Early flower 6"
Red clover 8-12 1/4 bloom 2" 3/4 to full bloom 8"
Alfalfa 10-15 full bud 2" Late bud 10"
Crownvetch 8-15 8-10" 3" Use grass timing 6"
Notes: Seeding rates can generally be reduced by 25 percent when grasses are mixed with legumes. Hay height is for first cutting. *Bulk Rate/Acre   **Pure Live Seed/Acre
Checklist for keeping a good grazing system
Grazing Rule of Thumb
Grass is too tall.
Grass is too short.
Grazing rule of thumb for cattle: If you can't see the cow's eyes (above), the grass is too tall. If you can see her nose (below), it's too short.
  • Graze to proper height at the right time. Use a “take half, leave half” guide to grazing, or consult the forage guidelines chart.
  • Check forage and livestock at regular intervals and move livestock according to the forage.
  • Allow pasture to rest periodically. Don’t leave livestock on pastures being rested.
  • Top-dress with fertilizer according to soil tests.
  • Maintain good fences.
  • Mow or hay paddocks before grass has set seed heads. Weeds or weedy grasses should be mowed when they reach a height of 6 inches, before they begin to compete for moisture and seeds mature.
  • Remove above ground pasture water systems in the winter and reinstall in the spring.
  • Review and adapt rotation schedule when herd size, or paddock number or size change.


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