Pasture Principles for Smaller Acreages

Pasture Planning

Begin with a written plan for your pasture. Your plan should contain these elements:

• A detailed assessment of your resources. Make a map of your farm or obtain one from your local Natural Resources Conservation Service (NRCS) office. Inventory your land, soil, water, fences, buildings, livestock, growing crops and forages, and machinery. Use a standard inventory form (Figure 1).

A good source of information is the NRCS soil survey for your land. Soil surveys provide basic information on soil identification and properties, land use, vegetation composition, and productivity. Soil surveys are available from your local NRCS or University of Idaho (UI) Extension office or online at https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm.

Also list the people involved with your pasture, including family members, hired labor, and other resource individuals such as your insurance agent, lender, accountant, etc. Note the management and production skills of these individuals. This is your team.

• Goals for your pasture and specific steps needed to accomplish the goals. Include production goals and specific forage production and livestock grazing plans. You may also include wildlife, soil resource protection, or other goals of importance to you. Written goals increase the likelihood of accomplishing those goals. Begin with at least one long-term goal (2–5 years) and one or more short-term goals (1 year). Short-term goals should support your long-term goals. Include specific objectives or action steps for each goal, a timeline to accomplish the objectives, and who will be involved in the effort.
• Budgets. A simple monthly cash flow budget will help you plan production and marketing throughout the pasture year. It will also help you focus on labor needs and capital investment plans. The UI provides cost and return estimates for producing crops and livestock in various parts of the state and also custom rate guides online at https://www.uidaho.edu/cals/idaho-agbiz. These resources can provide a starting point for your budget.
• Initial grazing plan for your pasture. Your pasture has a carrying capacity based on how much forage it can produce. It is important to balance pasture production with livestock consumption. You can get an idea of available forage from the previous owner or from your soil survey.

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Allowing livestock onto the pasture can supplement this effort, but be careful not to trample the seed too deeply into the ground on wet soils. Animal hoof action can firm the soil, cover seeds for seedling germination and growth, and provide small depressions to store water.

Establishing a new pasture may be necessary for much-depleted pastures or when converting from annual crop production. A new pasture may be established with no tillage (direct seeding), minimum tillage, or conventional tillage. A weed-free, firm seedbed is required.

Choosing Forage Species

Choose adapted varieties that the animals you plan to graze find palatable and that have characteristics that match your planned timing and intensity of grazing. Available water may limit the selection to drought-tolerant species. Local seed companies or UI Extension educators in your county can help you identify good varieties for your area. Including alfalfa, clover, or other legumes can increase protein levels and provide a source of nitrogen for plants.

Here are characteristics of common pasture grasses and legumes:

• Meadow brome—High seedling vigor, excellent palatability, heat and frost tolerant, regrows quickly after grazing.
• Smooth brome—Sod forming, establishes quickly, palatable, shade tolerant, slow to recover after grazing.
• Tall fescue—Bunchgrass, adaptable and productive, moderately palatable. Use endophyte-free seed.
• Orchardgrass—Bunchgrass, highly palatable, somewhat disease and frost susceptible, for irrigated or higher rainfall areas.
• Perennial ryegrass—Bunchgrass, establishes easily, short-lived, highly palatable, recovers well after grazing, tends to go dormant in summer.
• Timothy—Bunchgrass, moderate palatability, establishes quickly, best in wet areas and cool climate, slow to recover after grazing, does not tolerate overgrazing.
• Intermediate or pubescent wheatgrasses—Sod forming, highly palatable, grows in early spring and fall, drought tolerant. Use intermediate for higher rainfall areas and pubescent for lower rainfall areas.
• Tall, crested, or bluebunch wheatgrasses—These bunchgrasses are long-lived, palatable, with good early spring and fall growth. Choose adapted varieties for your site and rainfall.
• Altai or Russian wildrye—Long-lived, robust, variable palatability, withstands saline conditions. Often used for standing winter feed.
• Legumes—Alfalfa, clover (alsike, red, and white), sanfoin, sweetclover, cider milkvetch, and birdsfoot trefoil are possible choices for pasture. The choice depends on your management objectives and the legumes’ compatibility with grasses.

Legume-grass mixes will have higher yields and protein contents than grass alone and are less likely to cause bloating or grass tetany problems. Having many species in a mixture presents grazing management challenges, however. Consider a mixture with one or two grasses and one or two legumes. Local seed companies have pasture mixes that should work well in your location.

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Pasture Soil

Healthy soil is the foundation for productive pastures. Pasture plants obtain water and nutrients from pasture soil. Soil characteristics such as structure, permeability, organic matter content, pH, and fertility affect the ability of soil to provide necessary water and nutrients.

Soils are composed of mineral material and organic matter. In-between the mineral particles are pores filled with water, air, and soluble nutrients. Organic matter serves as a binder for mineral particles and contributes to good soil structure and water and nutrient holding capacity.

Soil pH

The ideal pH range for pasture soils is between 6.0 and 7.0, but pasture plants can tolerate a wide range of soil pH. Pasture grass yields are usually not reduced until soil pH drops below 5.1. Legumes are more sensitive to soil pH and grow best in the ideal pH range. Soils with a lower pH will not produce maximum legume yields. Whether to add lime to correct low soil pH is a cost/benefit decision that should take into account the availability and cost of lime and the projected increase in production from the application. To figure possible increases in production, look at production yields on local fields with pH in the “ideal range,” ask your neighbors or UI Extension educators, or consult data from UI test plots.

Organic Matter

Increased organic matter in soil enhances moisture and nutrient holding capacities and improves soil structure. Organic matter in pastures comes from plant and animal residues on the surface and in the soil. While you can spread compost or manure to boost organic matter, plant roots are the primary source of organic matter in pasture soils.

Well-managed grazing keeps pasture grasses tillering and productive, with more extensive root systems. Overgrazed pasture plants have pruned root systems (Figures 2 and 3). A pasture grazed to produce healthy pasture plants will maintain or increase soil organic matter.

Compaction and Erosion

Compaction and erosion are soil degradation problems. Compaction usually occurs when equipment operates on wet or moist soils. Pores are squeezed, making it difficult for air and water to penetrate the soil. Compaction can also be caused by livestock, particularly when soil is saturated and grazing is concentrated. Areas such as water supply, feeding, or mineral locations are particularly susceptible to compaction.

Erosion is the process that loosens or dissolves soil or rock materials and carries them away. Erosion is caused by wind and water. Erosion can be severe when the surface of frozen soil thaws. Rainfall and snowmelt have limited ability to permeate frozen soil and instead can wash away the thawed soil surface.

The susceptibility of soils to erosion depends on the amount of rainfall and its intensity, soil particle size, organic matter content, permeability, steepness and length of slope, amount of vegetative cover, type of crop, and management factors. Low-quality pastures have more bare ground and poorer soil quality, making them more susceptible to runoff and erosion.

Pastures often contain water sources such springs, wells, ponds, or a stream. Keep manures or eroded soil out of these water bodies.

Soil Fertility

Pasture plants require adequate levels of light, heat, air, water, and nutrients. When one of these factors is limiting, plant growth can suffer even when all other factors are adequate. It is important to identify the factor(s) limiting growth or yield in your pasture. When soil moisture conditions are satisfactory, nitrogen and phosphorus levels in the soil are often the factors limiting growth, yield, and forage quality. Potassium, sulfur, boron, and molybdenum can also be deficient in Idaho soils, but applications of these nutrients may or may not generate an economic response.

Nitrogen. Of all the nutrients, plants use nitrogen the most, causing it to be deficient in many grass pasture soils. Plants growing in nitrogen-deficient soils will readily respond to nitrogen fertilizer applications with increased yield and forage quality. When legumes are present, however, too much nitrogen can lead to a reduction in the legume fraction of the pasture. Also, nitrate-nitrogen not taken up by plants has the potential to leach into groundwater.

Phosphorus. Phosphorus may also be deficient in pasture soils. Since phosphorus has limited mobility in the soil, it is best to apply it when establishing a new pasture, mixing it well in the top 5–6 inches of soil. On established pastures, phosphorus can be broadcast on the soil surface. Apply enough to supply pasture needs for 2–3 years. Adequate phosphorus is especially important for pastures containing legumes.

Pasture Weed Management

Noxious Weeds

All pasture owners and managers must comply with the Idaho noxious weed law. Noxious weeds are classified in one of three categories: (1) early detection/rapid response, (2) control, and (3) containment. Your responsibility for controlling noxious weeds varies by classification. More information is available on the Idaho State Department of Agriculture website at https://invasivespecies.idaho.gov/plants/, or contact your county weed superintendent.

Weed Prevention

The first step in weed management is prevention. Beware of weed seed spread to your pasture by movement of hay, equipment, livestock, or wind. Use only weed-free seed and hay.

A properly managed, well-established pasture should have few weed problems. As pasture stands become depleted due to overgrazing, mismanagement, or stand maturity/succession, weeds will move in to occupy bare ground. Unless the problem causing pasture decline can be corrected, weeds will need to be controlled.

Scouting for Weeds

Before you undertake any control measures, scout for weeds in your pasture. Know your enemy. Careful inspection of the pasture to determine weed species present, their density, and location is time well spent. Pay special attention to the dominant weed species as well as occasional weeds, particularly perennials. Your weed control program should focus on controlling dominant weeds while preventing the occasional weed from spreading.

Pasture Grazing

Carrying Capacity and Stocking Rate

Carrying capacity and stocking rate are concepts that are used to determine the proper balance between livestock grazing and pasture plant production. Stocking rate is the number of grazing animals on your pasture for a given period of time. Animal unit month (AUM) is a concept that standardizes the expression of stocking rate. An AUM is the amount of feed a 1,000-pound lactating cow (one animal unit) will consume in 1 month, commonly 780 pounds of forage dry matter. Other grazing animals are expressed as a fraction of an animal unit based on their feed intake relative to the 1,000-pound cow:

• 1 cow = 1.0 animal unit
• 1 bull = 1.4 animal units
• 1 horse = 1.2 animal units
• 1 sheep or goat = 0.2 animal unit
• 1 llama = 0.3 animal unit

Carrying capacity is the stocking rate that maintains or improves your pasture plant, soil, and water resources given your grazing system. Carrying capacity depends on the total amount of forage produced and on the percentage of total production that can be harvested without harm to the pasture. Use soil survey data for your soil type as a rough estimate of forage production. The previous owner or local, experienced pasture managers can help you fine-tune your production estimate. Tools known as a rising plate meter or pasture stick can also be used to make this estimate.

Take Half, Leave Half

A grazing rule of thumb for stocking rate: take half, leave half. In most pastures, harvesting half of the total forage can be sustainable. If you manage the length of the grazing period and your stocking rate so that you remove half of the forage and leave half of the forage, and then allow a sufficient rest before regrazing, you will not exceed the carrying capacity for your pasture.

Suppose your estimate of forage production for a 4-acre pasture is 10,000 pounds of dry matter for a 4-month grazing season. First, determine how much of that production you will allow the animals to graze. Following the take-half rule,

10,000 lb × 50% = 5,000 lb of usable forage.

Next, calculate the total AUM available:

5,000 lb dry matter ÷ 780 lb dry matter per AUM = 6.4 AUM available.

Next, calculate the AUM available per month:

6.4 AUM ÷ 4 months = 1.6 AUM per month.

Finally, calculate your carrying capacity for sheep on this pasture:

1.6 AUM per month ÷ 0.2 AUM per sheep = 8 sheep per month.

So, your carrying capacity on this pasture is 8 sheep for a 4-month grazing period.

Practically, it is difficult to place a definitive figure on how many animals should be placed on a particular pasture. If you are managing your pasture correctly, the figure will vary from year to year based on the condition of the forage. Pasture managers should constantly check grass utilization and make adjustments in the stocking rate based on forage production and the amount of use. Too many animals on a pasture for too long can harm the resources resulting in poor livestock performance. Too few animals on a pasture means the resource will be underutilized.

Grazing Timing

Most land managers have a target turnout date they shoot for each year. Do not use a specific date such as May 1. Examine the grass and base your decision on the stage of grass growth. Allow at least 6 inches of grass growth before turning livestock in to graze. This will allow young grass plants to produce energy through photosynthesis and store some of that energy in their lower stems and roots.

Remove the livestock from your pasture when half of the forage has been consumed. If the forage grows back, you can graze it again. Leaving half of the forage will promote a healthy, vigorous, and long-lasting grass stand in your pasture.

Grazing Systems

The most common grazing systems for smaller acreages are the following: continuous, deferred, rest rotation, and rotation. Combinations and variations of these grazing systems also exist.

Continuous. Livestock producers using this system simply place the animals in one pasture and leave them there for the entire grazing season. This system, although common, can be very detrimental to the pasture. Livestock will heavily graze the most desirable species, allowing less desirable species to gain dominance in the pasture.

A useful modification is limit grazing. Livestock are allowed to graze for part of a day and are then returned to a drylot for the rest of the day to conserve the pasture. This is particularly useful with mature horses or other livestock on maintenance diets; they will consume more pasture in continuous grazing than they need.

Another way to limit continuous grazing is to allow livestock to graze pasture to a prescribed height and then move the animals to a drylot and feed them hay. Return them to the pasture when plants have regrown sufficiently to allow regrazing.

Deferred. A deferred grazing system uses the principle of not grazing a particular pasture for a specific period of time until plants reach a certain maturity level. This system works well in operations that have at least two pastures. The first pasture, pasture A, is grazed at the beginning of the grazing season the first year. The second pasture, pasture B, is left ungrazed at the beginning of the year. After a specific period of time, maybe a month or so, livestock are moved from pasture A to pasture B.

The second year, pasture B is grazed at the beginning of the year and pasture A is grazed later. Every year the pasture grazed first is alternated. See Table 1.

Rest rotation. The rest rotation system requires at least two pastures, but three or more are better because one pasture can be rested for a full growing season. In a three-pasture rest rotation system, the first-year livestock graze the first pasture, pasture A, then the second pasture, pasture B. The third pasture, pasture C, is rested. The second year, pastures B and C are grazed in sequence and pasture A is rested. The third year, pastures A and C are grazed and pasture B rested. The rotation then starts all over again.

In this three-pasture rotation, the pasture that is grazed first in the spring (the most stressful time to graze the plants) is then allowed to rest a full year plus a spring. The rest rotation system is useful for renovating pastures or stockpiling forage for late fall and early winter use (Table 1).

Rotation. This system is also known as management intensive grazing. It utilizes small pastures called paddocks. Livestock are rotated from one paddock to the next after they have grazed forage down to a specific level in a short period of time. Forage in previously grazed paddocks is allowed to grow back for regrazing later in the season when forage plants reach the appropriate growth stage. Rotation goes from paddock A, to B, to C, to D, and so on. This system seems to work best in areas where abundant moisture ensures regrowth of forage and available water sources for livestock.

Designing a Grazing System

When selecting or designing a grazing system, be sure to keep in mind the following:

• Number of pastures available
• Size of each pasture
• Fencing required to divide pastures
• Ease of moving livestock between pastures
• Water sources

The grazing systems outlined above are presented in ascending order of complexity, management intensity, and capital requirements. A properly managed management intensive grazing system will increase livestock production per acre and improve pasture and soil quality. But a mismanaged system can degrade pasture condition just as readily as continuous grazing.

Management goes beyond building fences and moving livestock: it includes understanding pasture plants and livestock-pasture interactions as a system. Choose the system that you have the skills and resources to successfully implement and maintain. Develop a plan to continue to improve your grazing system and move toward a more complex and productive system.

Regardless of the grazing system you select, time grazing to avoid grazing before plants reach a height of 4–6 inches. Allow 4–6 inches of regrowth before grazing again. Also closely control severity of grazing to avoid removing more than half of a plant’s leaf area.

There is a great deal of information available concerning the various aspects of grazing management. Many grazing practices and systems apply to all pastures, while some must be modified for smaller-acreage pastures. Use the principles outlined in this bulletin, along with your own experience and that of experienced grass farmers, to improve your smaller-acreage pastures.

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Further Reading

Pasture Grazing

Beetz, A. E., and L. Rinehart. 2010. Rotational Grazing. Fayetteville, AR: ATTRA. https://attra.ncat.org/product/rotational-grazing/.

Howery, L. 2016. Summary of Livestock Grazing Systems Used on Rangelands in the Western United States and Canada. University of Arizona Cooperative Extension Publication AZ1184. https://extension.arizona.edu/sites/extension.arizona.edu/files/pubs/az1184-2016_0.pdf.

Morrow, R., A. E. Beetz, and L. Rinehart. 2009. Paddock Design, Fencing, and Water Systems for Controlled Grazing. Fayetteville, AR: ATTRA. https://attra.ncat.org/product/paddock-design-fencing-and-water-systems-for-controlled-grazing/.

Mosley, J. C. 1992. “Designing Your Grazing System.” In Cow-Calf Management Guide and Cattle Producer’s Library, 3rd ed., 502–1. Moscow, ID: Western Beef Resource Committee. http://osu-wams-blogs-uploads.s3.amazonaws.com/blogs.dir/2753/files/2016/09/502-Designing-Your-Grazing-System.pdf.

Porath, M., and T. E. Bedell. 2006. “Grass Growth and Development Considerations for Grazing Management.” In Cow-Calf Management Guide and Cattle Producer’s Library, 4th ed., 505–1 (2014). Moscow, ID: Western Beef Resource Committee. https://webdoc.agsci.colostate.edu/ansc/CattlemansLibrary/505 COLOR.pdf.

Rinehart, L. 2018. Multispecies Grazing: A Primer on Diversity. Fayetteville, AR: ATTRA. https://attra.ncat.org/product/multispecies-grazing-a-primer-on-diversity/.

Pasture Management

Barnes, R. F., C. J. Nelson, M. Collins, and K. J. Moore, eds. 2003. Forages: An Introduction to Grassland Agriculture, Vol. 1. Ames: Iowa State Press.

Barnhill, J. (project coordinator). 2019. Small Pasture Management Guide for Utah. Logan: Utah State University. https://boulder.extension.colostate.edu/wp-content/uploads/sites/7/2019/11/Utah-pasture-guide.pdf.

Griggs, T. C., and P. E. Kingery. 1998. Performance of Forage and Conservation Grasses in Northern Idaho. University of Idaho Extension Bulletin 798. View PDF>>

Griggs, T. C., and P. E. Kingery. 1998. Performance of Perennial Forage Legumes in Northern Idaho. University of Idaho Extension Bulletin 802. View PDF>>

Kuepper, G. L., and A. E. Beetz. 2006. Pastures: Going Organic. Fayetteville, AR: ATTRA. https://attra.ncat.org/product/pastures-going-organic/.

Rinehart, L. 2020. Pasture, Rangeland, and Adaptive Grazing. Fayettville, AR: ATTRA. https://attra.ncat.org/product/pasture-rangeland-and-grazing-management/.

Rinehart, L., and A. Beetz. 2013. Pastures: Sustainable Management. Fayettville, AR: ATTRA. https://attra.ncat.org/product/pastures-sustainable-management/.

Shewmaker, G., ed. 2005. Idaho Forage Handbook. 3rd ed. University of Idaho Extension Bulletin 547. View PDF>>

Shewmaker, G. E., and M. G. Bohle, eds. 2010. Pasture and Grazing Management in the Northwest. University of Idaho Extension PNW 614. View PDF>>

Pasture Soils

Mahler, R. L. 1994. Liming Materials. University of Idaho Extension CIS 787.

Mahler, R. L. 2005. Northern Idaho Fertilizer Guide: Grass Pastures. University of Idaho Extension CIS 853.

Mahler, R. L. 2005. Northern Idaho Fertilizer Guide: Legume and Legume-Grass Pastures. University of Idaho Extension CIS 851.

Scott, D., and N. Prater. 2018. Nutrient Cycling in Pastures. Fayettville, AR: ATTRA. https://attra.ncat.org/product/nutrient-cycling-in-pastures/.

Shewmaker, G. E., J. Ellsworth, and S. Jensen. 2009. Southern Idaho Fertilizer Guide: Irrigated Pastures. University of Idaho Extension CIS 392. View PDF>>

USDA Natural Resources Conservation Service. 2003. “Managing Soil Organic Matter: The Key to Air and Water Quality.” NRCS Soil Quality Technical Note No. 5. Auburn, AL: Soil Quality Institute. https://www.blogs.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_050965.pdf.

USDA Natural Resources Conservation Service. “Web Soil Survey.” Local NRCS office or https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm.

Volk, J., W. Barker, and J. Richardson. 2003. “Soil Health in Relation to Grazing.” North Dakota State University Central Grasslands Research Extension Center. Fargo, ND. https://www.ag.ndsu.edu/archive/streeter/2003report/Soil Health in Relation to Grazing.htm.

Walsh, O., R. Mahler, and T. Tindall. 2020. Soil Testing to Guide Fertilizer Management. University of Idaho Extension BUL 915. View Article >>

Pasture Weeds

Beck, K. G. 2013. Weed Management for Small Rural Acreages. Colorado State University Extension Fact Sheet No. 3.106. https://extension.colostate.edu/docs/pubs/natres/03106.pdf.

Dufour, R. 2001. Biointensive Integrated Pest Management. Fayetteville, AR: ATTRA. https://attra.ncat.org/product/biointensive-integrated-pest-management/.

Hulting, A., and T. Prather. 2019. “Small Pastures” and “Weed Control in Pasture and Rangeland.” In Pacific Northwest Pest Management Handbooks [online]. Corvallis, OR: Oregon State University. https://pnwhandbooks.org/weed/pasture-rangeland.

Prather, T., S. Robbins, and D. Morishita. 2008. Idaho’s Noxious Weeds. 9th ed. (2018). University of Idaho Extension Bulletin 816. View PDF>>

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About the Authors

Kenneth Hart—University of Idaho (UI) Extension Educator, Lewis County

Randall Brooks—UI Extension Forestry Specialist

James Church—UI Extension Educator, Idaho County

Photo

Cover photo courtesy of Dave Powell, USDA Forest Service (retired), Bugwood.org

BUL 849 | Published September 2020 | © 2022 by the University of Idaho

Issued in furtherance of cooperative extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Barbara Petty, Director of University of Idaho Extension, University of Idaho, Moscow, Idaho 83844. The University of Idaho has a policy of nondiscrimination on the basis of race, color, religion, national origin, sex, sexual orientation, gender identity/expression, age, disability or status as a Vietnam-era veteran.