Farmers and ranchers are optimists by nature. They need to be, when they make the decision to feed their cows purchased feeds through the winter because they fed all their own hay during the summer. Or when they plant seed into dry, dusty fields, believing the rains will return.
On that optimistic note, let us assume your area will receive good moisture this winter and spring, and pastures that were parched last summer will emerge with new, green vigor. Should your grazing practices return to business as usual, or should last year’s drought continue to influence your management decisions?
The latter, says University of Nebraska agronomy professor Bruce Anderson, PhD. After suffering damage during the drought, plants need time to recover. Good moisture conditions could bring a nice green-up next spring, but looks can be deceiving. Carbohydrate reserves in plant roots likely are in short supply, and premature grazing could set the plants back. With that in mind, Anderson suggests delaying spring turnout for at least a couple of weeks beyond the usual date, even if pasture conditions look good.
Rancher Mark Frasier, whose family operates Frasier Farms near Sterling, Colo., also stresses the need to protect the health of forage plants as they recover. In the early part of the growing season, he says, managers need to be cautious about taking too much too early.
Frasier notes that on his family’s ranch, and in many other areas, native forage plants are genetically adapted for resilience to dry conditions. They recover once moisture returns, provided managers do not hamper that recovery. But if ranchers allow cattle to graze those plants too soon, before root reserves rebuild, they will come back slower the next time, and forage production for the entire year could be reduced.
Frasier also notes that pastures might have very little residual forage left from last season, meaning cattle will be grazing virtually all new growth instead of a mix of dried residual and green forage. This can result in more grazing stress on the plants. He plans to monitor pastures closely next spring and move cattle to prevent grazing from getting ahead of plant growth.
Anderson adds that in some areas ranchers grazed pastures that greened up following some late rains this fall. He suspects that fall grazing on late growth further depleted root reserves, which will hinder forage growth in the spring and leave plants vulnerable to damage from premature grazing. Wherever possible, he advises leaving that late forage growth ungrazed, allowing plants to rebuild root reserves for stronger growth next spring. Where cattle did graze that fall growth, plants might need extra recovery time in the spring.
Iowa State University animal scientist James Russell, PhD, also encourages later turnout dates. “I’m not usually a big proponent of creep-feeding,” he says, but this spring it could be a good option, along with supplementation of the cows to help delay turnout, allowing pastures a little more time to recover. Russell says grazing management becomes increasingly critical during and following a drought. With high precipitation, he says, you have a greater margin for error, but small mistakes in managing drought-stricken pastures can cause lasting damage.
Optimize soil fertility
Soil fertility is a starting point for pasture management, and Russell encourages ranchers to test pasture soils for pH, phosphorus and potassium. ISU research shows a direct relationship between soil phosphorus and forage productivity. And he recommends applying lime and fertilizer as soon as possible where needed, as it takes time to change soil pH and for phosphorus to become available to plants.
Anderson also recommends using soil tests and fertilizing improved pastures accordingly. Dry conditions will limit growth regardless of soil fertility, so he reminds producers to adjust fertilization rates based on moisture availability. In some cases, pastures that were fertilized last year could have high levels of residual nutrients in the soil due to limited plant growth during the drought.
Plan stocking rates
Once you do stock pastures, Anderson suggests setting stocking rates and schedules with the idea of harvesting less forage than usual, proportional to the level of precipitation. If the growing season provides “normal” precipitation, consider reducing forage utilization to 80 or 90 percent of normal, and likewise if precipitation is lower or higher than normal. Be acutely aware of soil-moisture status at the beginning of the grazing season, he says.
Frasier focuses more on turnout dates and grazing periods rather than stocking densities. He doesn’t believe it is necessary to reduce stocking rates dramatically if pastures green up quickly, but grazing periods might need to be shorter to avoid overgrazing. And as noted earlier, he’ll let moisture levels and spring growth determine turnout dates.
Russell encourages ranchers to incorporate more rotational or strip grazing wherever possible. In ISU trials this year comparing continuous-, rotational- and strip-grazing systems, pastures under continuous grazing were depleted by early September, while strip-grazed pastures, stocked at the same rate, remained productive into late October.
Weeds could become a major problem in some pastures this spring, Anderson says, as drought and overgrazing reduce the ability of desirable forages to compete. Pastures with areas of bare soil could experience a “cheat-grass storm” if they receive moisture this fall and winter. Weed encroachment could be visible now, if conditions have favored fall growth, and ranchers might have an opportunity for early control where they see weeds emerging. In most cases though, the weeds won’t appear until spring, and Anderson recommends monitoring pastures closely to make timely weed-control decisions.
Russell also recommends treating for weeds as needed and suggests planting annual grasses such as rye or triticale to out-compete weeds in sparse pastures. He also favors “frost seeding” with legumes, saying the drought potentially has a silver lining in that ranchers have an opportunity for this fairly simple method for improving forage quality and production. This method involves spreading seed on the surface of frozen soil in late winter, allowing the spring freeze-and-thaw cycles to create seed-soil contact for spring germination. Ground cover can limit the success of frost seeding, and it tends to work best on pastures with more bare ground, so it could be a good option in drought areas this year. Seed for legumes such as red clover can provide a relatively inexpensive option for frost seeding. Winter and spring moisture, of course, will play a major role in the success of establishing new forages.
Monitor conditions and growth
Ideally, ranchers have some type of monitoring system in place to help them identify trends and determine whether a pasture is improving, declining or stable. For some, memory of what a pasture looks like from month to month or year to year might suffice. But generally, a more structured system such as maintaining a photographic record of conditions at the same locations on the same dates every year will allow more objective and accurate assessments.
Once the grazing season begins, Anderson advises producers to pay close attention to rainfall and forage conditions and be prepared to make adjustments by moving cattle or reducing stocking rates as needed for long-term pasture health.
He also advises ranchers to monitor plant density along with plant height. Even where vertical growth is good, fewer tillers or shoots could mean thinner stands in drought areas. A side view from the road can be misleading, with the stand appearing denser than it really is, so Anderson reminds ranchers to get out and walk pastures, looking at plant density from above. Be conservative in your expectations for forage production, he says. It is better to err on the side of leaving some forage than on the side of overgrazing and wishing you had more forage.
Finally, Russell notes that last summer producers in many areas turned to early weaning to reduce grazing pressure and allow cows to retain body condition through the drought. If dry conditions persist this year, early weaning could again be necessary. But even if moisture conditions improve, producers might consider weaning their calves early as a means of reducing late-season forage use.