Question of the Week
I am pleased to provide you with information on forage varieties and dryland pasture management.
Dryland pastures can be very productive, but require good management to remain productive. Forage variety selection, planting technique and timing, and grazing management are crucial for sustained productivity. Plant varieties can be selected that are drought tolerant, winterhardy, and maintain high levels of nutrients well into the dormant season. These varieties can extend the grazing season and reduce the amount of stored forages fed during the winter.
In this letter I will address forage establishment, forage species selection, stockpiling, and grazing management.
Dryland Forage Establishment
Establishing dryland pasture grasses is often tricky. It’s really a matter of timing; getting the seed into the ground at the right depth at the right time to take advantage of spring rain or snowmelt. In the intermountain west, dryland grasses and forbs can be planted either in the fall or spring. If you choose to plant in the fall, ensure that the temperatures have cooled to below 40 degrees F to prevent seed germination too soon. The idea is to get the seed in before the snow falls, and take advantage of moisture from the spring thaw to hydrate the seeds for germination. If you plan to plant in the spring, it’s best to pick a time after spring thaw and before early summer. Summer in the intermountain west often finds dry periods in June and July, depending on your area. If grasses are planted too late they may not have enough moisture to get established. For best results coincide your plantings with spring rains.
Dryland grasses and forbs can be directly seeded into the soil with a range drill. This is often the preferred method in the spring as tillage quickly depletes soil moisture and organic matter. Fall tillage and planting would be appropriate if winter snow supplies moisture for soil hydration and seed germination in the spring.
For your area, I would recommend a mixture of grasses and forbs designed to establish and grow under dry conditions. A typical dryland mixture that should do well in your region is:
Intermediate wheatgrass or
Pubescent wheatgrass 5 pounds per acre
Russian wildrye 3 pounds per acre
Sainfoin 2 pounds per acre
Alfalfa 1 pound per acre
These should be planted ¼ inch deep on 6 to 10 inch rows. If broadcasting seed, double the seeding rate. More information on choosing plant varieties and species can be obtained from the Intermountain Planting Guide published by Utah State University Extension Publications. I do not know what the price is now, I paid about eight dollars for mine. You can get one by calling USU Extension Publications at 435-797-2251.
It is important on rangeland to defer grazing for at least one year after planting to allow grasses and forbs to establish and develop good root systems.
You might contact your area NRCS Conservationist for more information on plants that do well in your area. The USDA has a website with a searchable database of local offices. It can be accessed at http://offices.sc.egov.usda.gov/locator/app.
Extending the Grazing Season with Stockpiled Forages
Stockpiling is defined as letting forage grow during summer and defer grazing to the fall or winter. This is an effective way of providing winter forage in some areas and can reduce the need for harvested forage. If it reduces hay use at all, significant savings can be realized. This system works well for early winter when spring-calving cows are in mid-pregnancy. Stockpiled grazing can be followed with meadow feeding of high quality alfalfa hay prior to calving.
Stockpiling has been shown to work well given appropriate pasture management and efficient allocation of dormant pasture during the winter. Many grass species will maintain a relatively high nutrient content and palatability for several months after dormancy begins. Two extra months of grazing can significantly reduce the costs associated with producing and feeding hay. In some cases, producers have been able to utilize stockpiled forage and eliminate the need for hay feeding completely. This usually works better in climates where the dormant grass can be preserved longer under adequate snow cover, and/or because of reduced microbial decomposition caused by low temperatures and limited moisture.
Stockpiled forages can either be limit-fed (allowing only so many hours of grazing per day), or by strip-grazing with a movable electric wire or tape. Other options for feeding stockpiled forages are to swath them with a hay mower, and then rake them into windrows. Cattle can graze directly off the windrow during the winter by using an electric wire or tape to ration hay on a daily basis. This is similar to strip-grazing in that the wire is moved each day to expose a predetermined amount of forage for grazing. This method, while still relying on a tractor to cut and windrow the hay, reduces the amount of fuel, materials, and hay equipment needed for bale and feed hay by eliminating the baling process altogether. This method works best in dryer regions where weathering is less likely to reduce the nutritional quality and palatability of the hay.
Altai wildrye (adapted from Smoliak, et. al.)
Altai wildrye is a native of western Siberia and the Altai Mountain region between Siberia and Mongolia. It thrives well on semi-deserts, steppes and saline soils. It is an excellent pasture grass that extends the grazing season into the fall and winter.
Altai wildrye has good curing qualities, and its erect growth makes it especially useful for late fall and winter grazing. The aftermath from seed production is nutritious, and can be used for fall and winter pasture.
Although the growth of Altai wildrye is coarse, cattle and sheep find it very palatable. It has the ability to retain a high nutritive value throughout summer, fall and into winter. Cattle have made satisfactory gains in September and October on Altai wildrye pasture saved for fall grazing. The erect, basal leaves of Altai wildrye will project above shallow snow and remain erect in deep snow, forming a bridge across the plants, and allow cattle to remove the snow with their muzzles and graze the forage underneath. It produces well, being somewhat better than Russian wildrye in yield and protein content. Also, it produces better quality forage than most other species at both the flowering stage and the mature or cured stage of development. To increase pasture production, include alfalfa with Altai wildrye in alternate rows or in a cross-seeded pattern. In dry areas the rows should be about 36 inches apart, and in moist areas about 18 to 24 inches apart.
Drought-Tolerant Cool-Season Perennial Bunch Grasses (adapted from Smoliak, et. al.)
Pubescent wheatgrass is a long-lived, sod-forming grass. It has slightly more drought tolerance and ability to spread by rhizomes than intermediate wheatgrass. The plants grow erect with a heavy growth of basal leaves. Stems grow to a height of 3 to 4 feet and produce seed heads that are 4 to 8 inches long. The plants, seed heads and seeds are somewhat hairy.
Seeds of pubescent wheatgrass and intermediate wheatgrass are frequently found as a mixture. The two species readily cross-pollinate. It is more drought tolerant and has more winterhardiness than intermediate wheatgrass. It is useful for hay and pasture. Its outstanding feature is its ability to stay green into the summer months when soil moisture is adequate.
Intermediate wheatgrass has a deep-feeding root system as well as creeping root stalks. Under irrigation, it is an aggressive sod-former. Under dryland conditions, it appears more like a bunchgrass. It is especially suited to seeding in mixtures with alfalfa because it usually has not flowered when alfalfa is ready to cut. For this reason, the hay cut from the mixture is of excellent quality.
In the drier areas, intermediate wheatgrass yields more than smooth bromegrass and crested wheatgrass for the first three crop years, but then productivity declines. It can be used for hay or pasture in areas where annual rainfall is at least 14 inches.
Russian wildrye is a large, cool-season bunchgrass that is a long-lived perennial. It has an abundance of long, dense, basal leaves that are 6 to 18 inches long and up to 1/4 inch in width. Plants vary from light to dark green, with many shades of blue-green. The erect, naked stems, about 36 inches tall, have flowering heads that form a dense, erect spike. The seed shatters very readily at maturity. The seed is about the same size as crested wheatgrass seed. Germination is high (but slow) and the seed remains viable for five to six years. It may take as many as three years to get a stand from a single, successful planting.
The roots are fibrous and may penetrate to a depth of 8 to 10 feet. About 75 percent of the total roots are in the surface 6 inches, but they have a wide, horizontal spread and may draw heavily on moisture for a distance of 4 to 5 feet. Its long season of growth and its vigorous soil-feeding habit make this species an excellent competitor with weeds once the grass is well established. Wide row plantings (18 to 36 inches) produce more forage than narrow rows.
Russian wildrye is exceptionally tolerant of cold and drought and is highly tolerant of salinity, and is fairly tolerant of alkalinity. Generally, Russian wildrye can be grown successfully wherever crested wheatgrass is grown, but it is primarily a pasture grass.
Russian wildrye requires special attention during the year it is seeded since it is very difficult to establish. It must be planted on a firm, weed-free seedbed at 1/2 inch depths or less.
This grass is well adapted for use as pasture in dry areas, and established stands are more or less permanent. It is as long-lived as crested wheatgrass. The forage is very palatable, having a longer growing period than most dryland grasses with an ability to cure on the stem. This allows for a long grazing season. It is also very tolerant of grazing and regrows quickly after clipping. Although grazing can continue from early spring to winter, it is frequently best to graze this grass lightly in the spring, and save most growth for late summer and fall when other grasses are unproductive or low in quality. It remains palatable and of adequate nutritive quality for mature stock on winter maintenance rations.
Wide row spacing increases production. Yields are also increased by seeding mixtures with legumes. Seeding the legume in alternate rows or cross-seeded rows decreases competition from Russian wildrye.
Introduced Cool-Season Perennial Legumes
Alfalfa (adapted from Smoliak, et. al.)
Alfalfa is very palatable and withstands grazing quite well. Bloat may be a problem, but the hazard is diminished if grazing is delayed until after the bloom stage, or the mixture consists of 50 percent or more grass and rotational grazing is practiced. For dryland pasture plantings (as opposed to irrigated hay meadow plantings), use a more winterhardy variety.
Sainfoin is a cool season perennial legume that is adapted to arid regions that receive as low as 13 inches of annual precipitation. It is considered to be non-bloating and performs well on dry sites. It is generally less productive than alfalfa, and not as long-lived, but when added to a good grass mix, such as pubescent wheatgrass or intermediate wheatgrass, will provide high quality forage during the growing season. It will also make a considerably good dormant season forage if grazed within a month of first frost, before it looses all its leaves to shatter.
Sainfoin is very drought tolerant and winter hardy, making it ideal for eastern Washington. It does not tolerate heavy grazing, however, and must be used within a proper rotational grazing system. Make sure that sainfoin has adequate re-growth time between grazing events and prior to first frost to maintain the stand.
For best results, use a bacterial inoculant on the seeds prior to planting, as this will greatly add to its ability to fix nitrogen and remain productive throughout the year. Sainfoin is very palatable and nutritious, and is best taken as a hay crop when between half to full bloom. Phosphorus fertilization will increase stand viability.
Plant sainfoin at a depth of one-half inch, at a rate of one pound per 10 or so pounds of grass seed for irrigated pastures, and about two pounds for every ten pounds of grass seed for upland or dry pasture settings. For irrigated fields it is best to plant on a prepared seedbed. However, for upland and dryland conditions use a no-till range drill to ensure proper seed to soil contact.
Prescribed Grazing on Rangeland
Prescribed grazing is the method of applying observation to management, observing some more, and then adjusting as needed. There are five steps in developing a grazing plan. They are (1) Inventory, (2) Define Goals, (3) Determine Grazing Units, (4) Develop a Grazing Schedule, and (5) Development of a Monitoring and Evaluation Plan.
This is for gathering baseline information to allow you to make appropriate decisions about land and pasture use. Obtain soil maps from your NRCS office and mark appropriate land forms, soil types, and fences and paddocks. Find out what plants are in each pasture, and evaluate the pastures based upon a condition score. Utilize features such as key species, percent canopy cover, amount of bare ground, presence of noxious weeds, annual forage production in pounds per acre, and amount of residue to determine pasture condition and productivity.
Make a list of what you want to accomplish. This will be a list of your expectations and will guide you in making plans and decisions. Do you want to improve the economic value of the ranch? Maintain wildlife habitat? Improve water quality and quantity? Reduce noxious weeds? Also consider available acreage and the amount of time you have to put into this project.
Determine Grazing Units
Divide the pastures into units that you can rotate animals through. This will allow you to rest pastures and allow for re-growth following grazing. It will also allow you to rotate grazing on a seasonal basis as well. Determine how much forage is available in each grazing unit and map it out. Note key species, percent cover, water availability, facilities, and other aspects important to you. Remember that livestock should always be within at least two hours walking distance from water. This will help you to determine grazing unit size (for large parcels).
Develop a Grazing Schedule
This will be a graphic illustration of your plans for grazing each unit during the grazing season. Develop the schedule based on your total Animal Units (AUs) and available Animal Unit Months (AUMs) in each unit. If you have a 100 acre pasture with 2 AUMs per acre, you have 200 animal unit months of forage available. At 50 percent allowable use, cut it in half to 100 AUMs. This means you have enough forage available to feed 100 animal units for one month. Or, said another way, 50 animal units for two months, 33 for three months, and so on. For more detailed information on calculating AUM’s see the Montana Grazingland Animal Unit Month (AUM) Estimator located at: http://www.mt.nrcs.usda.gov/technical/ecs/range/technotes/rangetechnoteMT32.html
Important concepts here are duration of grazing and time for re-growth. Some range ecologists and managers believe that grazing intensity is also important, and it is. A plant needs to have green leaves left after grazing for photosynthesis and subsequent re-growth. However, others feel that grazing severity isn’t as important as re-growth time. Whichever you choose, it is important to remember to allow plenty of time for adequate re-growth before the animal gets to bite a plant a second time.
Take a look at the native plants on an upland range site if you have the opportunity. Some, like bluebunch wheatgrass and rough fescue, are large-statured and can handle several bites from an animal in one grazing event. Some, like Sandburg bluegrass and Idaho fescue, are smaller, and one bite is all it takes to reduce the plant to stubble. Cattle, especially, tend to graze severely, so don’t get too caught up in how much they take off. Strive for 50 percent use, and allow for re-growth. For some sites on dry ranges, this will mean one grazing event per year. For areas with more moisture, you might be able to return every 15 to 30 days for another grazing event.
This is the most neglected part of range management, and the most important. A good monitoring system will allow you to check how your management decisions are working on the ground. It will allow you to determine, for instance, if a particular grazing plan is having the desired effect over time. A monitoring plan will often involve a few important evaluation criteria, such as plant species composition, percent cover, and frequency of species. By comparing these measurements over time, you can start to see trends, and by comparing them to your grazing system, you can alter and adjust where you need to in order to arrive at your goals.
Record keeping is a very important part of pasture monitoring. In addition to recording the afore-mentioned physical measurements, keep track of when livestock enter and leave a pasture, what if any materials or chemicals are used, re-vegetation or weed control treatments, and observations on cattle health while in the pasture. This information will be extremely useful in refining your grazing plans.
Managing for Drought
Drought is a natural ecosystem process. The concept of an “average” or “normal” precipitation or temperature is a fabrication that humans use to try to understand complex systems and attempt to predict behaviors and outcomes. Whether in a humid zone or an arid environment, a producer will experience relative wet and dry years. Dealing with the dry years is a real challenge to livestock operations that rely on water to grow the plants and recharge the aquifers and streams that feed the animals. Having a drought plan is a very important component of a well-thought out farm or ranch management plan.
A drought-management option that deserves serious consideration is for a producer to maintain livestock numbers at 75 percent of carrying capacity for “normal” years, and utilize the extra forage in wet years for high value animals such as stockers. In dry years the pastures will be better able to accommodate current livestock numbers. Another option is to slow down rotations during dry years, thereby allowing more paddock or pasture rest time. This option can be effective especially when the herd is split between different pastures to minimize the impact on drought stressed plants.
If you must de-stock during drought, consider which animals should be the first to go. Do you have low producing females? Do you have older calves that can be sold as stockers? Whichever you do, be sure not to de-stock too late. Pasture that is overstocked and drought-stressed is hard to repair whereas a cow herd can be bought when rains return.
See the ATTRA publication Pasture, Rangeland, and Grazing Management
Smoliak, S., R.L. Ditterline, J.D. Scheetz, L.K. Holzworth, J.R. Sims, L.E. Wiesner, D.E. Baldridge, and G.L. Tibke. Montana Interagency Plant Materials Handbook. Montana State University. http://animalrangeextension.montana.edu/Articles/Forage/Species/MTSpecies.htm
USDA. 2007. Washington State Plant Materials. USDA-Natural Resources Conservation Service. Website accessed March 1, 2007.
Sayre, Nathan and Kirk Gadzia. 2004. Rangeland Health and Planned Grazing Field Guide. Santa Fe, NM: Quivira Coalition. 1413 Second Street, Suite 1, Santa Fe, New Mexico 87505. 505-820-2544 http://www.quiviracoalition.org/
USU Extension. Intermountain Planting Guide. Utah State University Extension Publications. 435-797-2251.
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