In range management, regular, systematic monitoring of rangeland health and productivity can determine if a pasture has problems and identify specific problems and their causes. Once you have identified shortfalls, how do you solve them?
Problems typically identified in a rangeland monitoring process include:
- sparse ground cover/low production
- signs of soil erosion
- soil crusting resulting in poor seed-soil contact
- slow incorporation of plant litter into soil
- poor water cycling
- poor nutrient cycling
- undesirable species including unpalatable or toxic plants
- inadequate species diversity
Often the most practical and most effective tool for resolving pasture-health problems is your cattle herd. "Ranchers cannot afford to spend a lot of money improving their rangeland," says University of Wyoming range management specialist Mike Smith. "They are left with using their cattle to influence rangeland health by manipulating numbers, stock density and timing." Specific solutions can include reducing or increasing stocking rates, lengthening or shortening rest periods, or using short-term, intensive animal impact or herd effect to intentionally disturb the soil surface in a given area. Other potential management tools include fire, mechanical impact, seeding or chemical impact.
Range management consultant Charlie Orchard, who operates Land EKGr in Bozeman, Mont., notes that each of these tools has a role in solving rangeland problems. In most cases though, he favors grazing management as the most practical and sustainable method for restoring and maintaining rangeland health. Fire, for example, can be an appropriate tool in cases where excessive standing dead forage or undesirable plants inhibit growth. But Mr. Orchard believes burning can be misused, acting as a substitute for more sustainable practices. Burning advances mineral flow at a rapid pace by reducing dead plant material to ash. Quick reduction of the canopy and an infusion of soil nutrients promotes rapid regrowth, but that growth comes at the expense of organic material that otherwise would return to the soil. Cool spring burns usually minimize these concerns.
Dr. Smith notes that in many such cases, intensively grazing an area can speed up nutrient cycling by putting litter and manure in contact with the soil surface. Hoof action can improve water cycling, especially on heavier soils where hoof imprints trap water for absorption reducing runoff. Dr. Smith adds that people tend to think of overgrazing as the primary cause of declining rangeland health, but undergrazing in pastures, or in parts of pastures, often is an equal source of problems.
To effectively use cattle in managing rangeland health, ranchers need a system for controlling where and when cattle graze. Ideally, this involves intensive rotational grazing with the flexibility to either move fencing or herd cattle and adjust stocking rates to account for differences in pastures. Managed properly, a rotational grazing program allows cattle to efficiently graze high-quality forage and allows the pasture enough recovery time to return to that productive state between grazing intervals.
Pasture growth consists of three phases. During phase one, when plants just begin to grow in the spring or following grazing, the quality of forage is high, but the quantity is low. Phase two features high quality and high quantity. During phase three, the quality of forage declines, although the quantity remains high. Ideally, pastures should be grazed during phase two, when high quality and quantity combine for the most energy efficient grazing. Overgrazed pastures tend to remain in phase one while undergrazed pastures tend toward phase three.
A remedy for overrest
During the late summer of 1998, Mr. Orchard worked with ranch manager Diane Palm to initiate a rangeland-monitoring program at Elk Mountain Ranch, Elk Mountain, Wyo. One pasture chosen for monitoring, designated "Boxcar," had lain idle for over two years. Ms. Palm wanted to bring the area back into production for grazing, but needed objective information on which to base management decisions such as grazing intervals and stocking density. Results of the initial measurements provide a basis for decision-making, and on going monitoring at the same sites will provide feedback on the results of those decisions.
Based on Land EKGr data collected during the initial monitoring, Mr. Orchard's report provides a baseline of the pasture's current condition, goals for future production and a set of recommendations for achieving those goals. A primary goal is to increase forage production in the pasture to 800 pounds per acre from the current 450 pounds per acre.
Ratings for indicators of pasture health, plotted on a Land EKGr "Ecograph," illustrate which aspects of the ecosystem need improvement. Several signs indicate that after more than two years without grazing, the pasture shows signs of overrest.
The soil surface at the time of the first survey consisted of 45 percent basal plant cover, 31 percent bare ground, 20 percent litter cover and 4 percent rock. A primary goal of the management plan will be to increase the percentage of soil covered with plants and litter while reducing bare ground to 15 percent or less. Mr. Orchard also would like to increase the percentage of grass species while reducing the amount of shrub influence.
To achieve these goals, he recommends initiating a controlled-grazing program. For the 1999 season, he suggests grazing the pasture for three to five days in late May, and for 10 to 14 days in late fall, using a stocking density of three to five animals per acre. The plan will require some additional fencing or herding and water development to divide the 600-acre pasture into smaller grazing cells.
Grazing the pasture at those intervals, Mr. Orchard explains, should have the following results:
- Improve mineral flow and soil organic matter by adding manure nutrients to the soil.
- Improve mineral flow through hoof action bending and breaking plants, increasing contact with soil.
- Improve water cycling by allowing more water to seep into the soil.
- Create more germination points by breaking up surface crusting and increasing contact between litter and soil.
- Dislodge seeds and allow better seed-soil contact through hoof action.
- Increase the number of phase-two plants available for the next grazing interval.
Following these guidelines, the ranch will be able to improve the health and productivity of the pasture just by using cattle as management tools. No chemical, mechanical or fire impacts are necessary. On going monitoring of the site will allow them to measure results and make appropriate adjustments.
How "herd effect" can stimulate grass production
Stan Parsons, CEO of Ranch Management Consultants Inc. and founder of the Ranching for Profit Schools, defines herd effect as the excited trampling of a mob of animals. Dr. Parsons distinguishes this from stock density, which is the concentration of animals per unit area of land. The stock density of 1,000 steers on 10 acres of land is the same as for one animal on 435 square feet of land, but the effect on the land is different with the herd creating a greater impact.
1. Early May 1997: This pasture has serious problems, with excessive bare ground and sage cover. Desirable plants are few, particularly young plants. To resolve these problems, Idaho's Double-D Ranch allowed forage to stockpile the previous fall then applied brief, high-density grazing with 900 cattle in late April. Ranch managers then allowed the area to rest through the season until late September.
2. July 3, 1997: After two months of rest, the pasture shows considerable improvement with young grass plants filling in between the sage. Hoof action from the intensive grazing in May dislodged seeds and created germination sites.
3. July 17, 1998: One year later, the health and productivity of the pasture have improved dramatically. Bare ground and sage cover have decreased in favor of grass plants. Production of desirable forage has increased from 100 pounds per acre to more than 450 pounds per acre. This achievement resulted entirely from using strategically timed animal impact and rest. The only cost to the rancher was time invested in planning.
University of Wyoming range management specialist Mike Smith says for many ranchers, setting up photo points can be an effective range monitoring system. Determine specific objectives for each photo point and take a picture every year around the same time. This can be enough to indicate whether management strategies for each site are resulting in an improvement, decline or no change.