Pasture Production and Grazing Information
Natural Resources Conservation Service /
Prescribed
Grazing
Helping People Help the Land
Bryan Zone Job Sheet – 528-1
Revised 03/07
Pasture Production and Grazing Information
Pasture Production
Many small land owners plan to run livestock on their land. If you are one of those people, you need to know how much forage you will need and how much forage your land will produce. Forage is what your animals consume by grazing. Forage production is measured in animal unit months (AUMs). One animal unit month of grazing is equivalent to the amount of forage consumed by a 1000-pound AU in one month. This amount is usually estimated at 790 lbs. You need 12 AUMs (9480 lbs.) of forage and/or feed to support one animal unit for a year. See “How Much Grass Do You Need?” for a comparison of average forage and feed requirements.
How Much Grass Do You Need?
MatureAnimal / Feed (Hay)
Tons / Month / Forage AUMs of
Grazing / Month
1 Cow / 0.39 / 1.00
1 Horse / 0.49 / 1.25
1 Sheep / 0.08 / 0.20
1 Goat / 0.06 / 0.15
1 Llama / 0.12 / 0.30
1 Fallow Deer / 0.06 / 0.15
1 Axis Deer / 0.06 / 0.15
Perennial warm season grasses make up a large portion of a grazing animal’s diet. There are two basic groups of forage grasses. Native grasses, which include little bluestem, switchgrass, and Indiangrass, are naturally occurring grasses that require little additional fertility once established, but require good grazing management to maintain. Their yields are fairly low compared to fertilized introduced grasses and will vary based on the natural fertility of the soils.
Introduced grasses, which include hybrid bermudagrass, common bermudagrass, and bahiagrass, are grasses that originated in other countries and were brought to the U.S. for forage production. They have been bred or selected for qualities like response to fertilizer, drought tolerance, etc. With added fertilizer introduced grasses will produce more forage than native species.
What Is Your Pasture and Hay Production?
Feed (hay)Tons/Acre / Forage
AUMs**/Acre
Native Grass* / 0 - 2.0 / 0.2 – 2.0
Unfertilized Introduced Grasses* / 0.5 - 1.5 / 0.6 - 1.7
Introduced Grasses with
Recommended Fertility* / 3 - 7 / 3.4 - 8.0
*Production will vary according to natural fertility of the site, climate, and species. ** AUMs assume that 45% of the total grass produced is consumed be livestock; the remaining portion is lost to grazing by trampling, fouling, or grazing requirement of the grass.
Before making a decision on managing your existing native grasses or establishing introduced species your land should be evaluated by a competent professional to determine its production potential, determine species suitability, and to estimate the costs involved in whatever management strategy you choose. Consult your local Natural Resources Conservation Service office for information sheets and assistance.
Grazing Management
Warm season perennial grass production in the eastern half of Texas occurs from April through October. Monthly production is low in the early spring and late fall due to cool temperature, and production is often low in late summer due to dry weather. Hay and/or other feed may be needed during these periods of slow growth. Grazing should be initiated in the spring when bermudagrass and bahiagrass reach a height of four to six inches; native grasses (little bluestem, switchgrass, etc.) should be allowed to reach 8 to 12 inches prior to grazing.
Use of the grasses for forage should be accomplished by allowing the livestock to graze one pasture for a period of time and then moving (rotating) the livestock to another pasture after the planned grazing period, or when they have reduced the majority of grass to the minimum grazing height. The pasture they are moved from should then be rested for the recommended period or the grass has recovered to the recommended height before grazing.
The minimum recommended grazing height for bermudagrass and bahiagrass is 3 - 4 inches, and for native grasses the range is from 4 - 8 inches. Generally the planned rotation and rest period for bermudagrass and bahiagrass is 21 - 28 days, and the planned rotation and rest period for native grasses is 30 - 45 days. The amount of time the livestock will remain on one pasture and the rest period is variable throughout the year, depending on rate of grass growth, which is determined by time of year, temperature, rainfall, etc. You may also wish to keep your livestock off of some of your pasture so that it can be harvested for hay. The interval for hay harvest is the same as for grazing, providing that growth is adequate to provide enough grass for harvest.
Typical warm season grazing availability.
Months
A / M / J / J / A / S / O / N / D / J / F / MG/F / G / G / G / G / G / G / G/F / F / F / F / F
G / Graze / G/F / Graze and Feed / F / Provide Feed/Hay
Typical warm season monthly grazing schedule
For a 5-pasture system.
Pasture / Grazing Period1 / Grazing Period
2 / Grazing Period
3 / Grazing Period
4 / Grazing Period 5
1 / G / Rest / Rest / Rest / Rest
2 / Rest / G / Rest / Rest / Rest
3 / Rest / Rest / G / Rest / Rest
4 / Rest / Rest / Rest / G / Rest
5 / Rest / Rest / Rest / Rest / G
Warm season grasses become dormant in the late fall and winter, so supplemental or complete feeding may be required from November through April. Hay, which can be made from your excess production in the summer or purchased from others, will be fed in the winter. In relatively warm winters feeding is reduced due to a longer growing season for the warm season grasses. Another option for the winter is to establish cool season annual grasses and/or clovers by over seeding some of your pastures, or planting them on a prepared seedbed. Cool season grasses include ryegrass, oats, wheat, and rye, and clovers include, ball, crimson, arrowleaf, berseem, and rose clover. These plants if successfully established will provide some forage during the fall and early winter, but the bulk of their growth will occur in early spring. These annual forages may be grazed short, but rest is necessary to allow regrowth. In the late spring graze or mow to remove excess growth and reduce competition with your warm season perennial grass.
Typical cool season grazing availability
Months
N / D / J / F / M / A* / M*F / G/F / G/F / G/F / G/F / G / G
* Pastures may need to be subdivided into small units in order to get maximum use of the cool season forage during this peak growth period.
Cool season annual grasses or legumes over-seeded on
warm season pasture to provide some winter grazing and reduce
amount of hay to be fed.
pHRange / Soil
Adaptation / Cold
Tolerance
Oats / 5.5 - 7.5 / Widely Adapted / Poor - Fair
Wheat / 5.5 - 8.0 / Widely Adapted / Good
Rye / 5.5 - 7.0 / Sandy - Loamy / Good
Ryegrass / 5.5 - 8.0 / Widely Adapted* / Good
Crimson Clover / 5.0 - 7.0 / Sandy - Loamy / Fair - Good
Arrowleaf Clover / 5.5 - 7.0 / Sandy - Loamy / Fair - Good
Rose Clover / 5.5 - 8.0 / Widely Adapted / Fair - Good
Berseem Clover / 6.0 - 8.0 / Loamy - Clay* / Fair - Good
Ball Clover / 5.0 - 8.0 / Widely Adapted* / Fair - Good
Hairy Vetch / 5.0 - 8.0 / Widely Adapted / Fair - Good
White Clover / 5.5 - 7.5 / Loamy - Clay* / Good
* Can tolerate poor drainage, others need moderately well to well drained soils.