Drought Management and Recovery for Pastures and Hayfields
A good portion of Maryland has been under abnormally dry or drought conditions for much of the summer, and dry conditions continue to persist in some areas across the region. For many farms, hay yields have been low, pastures have been grazed short, and producers will likely have to feed more hay than usual. Although some areas have received occasional scattered showers, for many forage recovery will require more than a few rain showers to return adequate moisture to the soil profile.
Drought conditions hamper forage growth and productivity because a lack of moisture suppresses plant growth and hinders root growth and development. Unfortunately, there is little that can be done during a drought to increase forage growth. However, proper management during and after a drought can minimize impacts, allow pastures and hayfields to rebound faster once moisture is sufficient, and mitigate any adverse long-term effects.
During Drought Conditions
- Use rotational or strip grazing to extend grazing on any remaining forage. Make the most of any remaining forage by allocating pastures in strips or paddocks large enough for no more than 2-3 days of grazing at a time. Smaller allocations will increase the utilization of existing forage and minimize trampling or waste. Temporary fencing is a good investment and a great tool for accomplishing this.
- Avoid overgrazing. Drought conditions weaken plants and essentially amplify the effects of grazing. When faced with a forage shortage, it is tempting to leave livestock on the pasture until every bit of green is eaten; however, heavy grazing or allowing animals unlimited access to pastures during drought can severely stress plants. Grazing removes photosynthetic tissue; with the growth of new leaves limited by drought conditions, plants are forced to utilize more of their stored energy reserves, which can be quickly depleted over time and reduce plant survival. Maintaining an appropriate residual grazing height will preserve stored carbohydrate reserves and shade and protect the soil surface, moderating soil temperatures and conserving any remaining soil moisture. Also, remember that top growth mirrors root growth, meaning continued overgrazing causes weak, shortened roots that will further slow recovery. Drought-stressed pastures will recover much more quickly once moisture returns if not overgrazed.
- Avoid cutting hayfields or mow high. If a limited amount of regrowth is present, cutting the crop will likely intensify drought stress and could do more damage to the stand. The little bit of growth present is helping to shade the soil surface and conserve any remaining soil moisture. If regrowth is significant enough to make harvest worthwhile, consider mowing at a higher cutting height to maintain plant reserves and minimize increased soil temperatures and adverse effects on root growth. Leaving more residue in the field will minimize temperature fluctuations and allow hayfields to recover more easily once rains resume.
- Provide longer rest periods. Reduced plant growth during drought means rest periods for pastures and hayfields will need to be longer. When plants are stressed by lack of water, it is more important than ever to make sure regrowth is not grazed or harvested until enough new leaves have formed to support the root system. Under drought conditions, plants that are more rested and have been allowed to build up energy reserves will undergo compensatory growth when rainfall finally comes. In contrast, plants frequently grazed or harvested during drought will regrow much more slowly.
- Hold off on applying additional fertilizer. Fertilizer inputs should be reduced or stopped during periods of prolonged drought. Moisture is needed to dissolve top-dressed fertilizers before they can move into the soil and the plant. Delaying fertilizer applications until moisture is present or imminent can increase efficiency.
- Scout for new areas to graze. Look for rented land, new pastures, or ungrazed areas that could be used for grazing to help stretch forage supply. Consider the possibility of renting unused pastures from nearby landowners; additional pasture rent might be less expensive than buying hay and feed.
- Utilize annual forages where possible. Drought-tolerant summer annual forages like sorghum, sudangrass, or millet will produce more forage under drought conditions than cool-season perennial stands. If annual forages have already been established, continue utilizing those stands as long as possible to protect perennial stands. Stay mindful of nitrate and/or prussic acid toxicity risks, particularly with the forecast for upcoming frost potential. At this point in the year, we are mostly beyond the window for establishing annual forages to use this fall, but cool-season annuals could still be established for early spring grazing or harvesting.
- Be prepared to provide supplemental feed. When pastures have not grown back enough to support viable grazing, it is best to confine animals in a sacrifice area and provide hay or other supplemental feed. When choosing a sacrifice area, consider an area that is already in poor condition or in need of some additional fertility, as this area will likely need to be renovated after the drought breaks.
- Protect hay during storage and feeding to reduce waste. Make the most of hay resources by minimizing hay losses during storage and feeding. Hay should be stored up off the ground and covered. Feed hay in rings or hay feeders to reduce hay waste. Unrolling hay typically increases hay waste unless done on a limit-feeding basis. Hay can also be unrolled and protected by placing a single-strand electric fence wire down the length of the line of hay.
- Utilize crop residues or cover crops. There may also be opportunities to utilize crop residues or cover crops established in crop fields for additional grazing or harvested forage. Consider testing crop residues for nitrates and feed value; in general, feed values for crop residues should be assumed to be low, but cover crops may provide higher quality forage. Agreements between livestock/forage producers and crop farmers should be considered for this option.
- Cull or wean early. If a forage shortage looms, consider reducing herd or flock numbers early. Effective livestock producers constantly assess and monitor their forage inventory, and this is never more important than when rain is scarce. Reducing the herd size will decrease forage demand and prolong existing forage resources. While not always an easy decision, animals that are old, open, in poor condition, or have poor disposition could be considered for de-stocking; a drought is not the time to carry unproductive animals. Also, consider weaning or selling calves or lambs earlier. Dry cows or ewes have lower nutrient requirements and reduced forage intake compared to lactating dams and can make better use of lower quality forage.
Following Drought Conditions
- Evaluate stand condition. Assess pastures and hayfields for damage. A thorough assessment can help determine which fields will recover, which may need overseeding or other inputs, and which (if any) require a complete renovation. Do not rush to renovate fields following a drought; wait until green up to assess potential recovery and decide whether or not to renovate. As a very general rule of thumb, stands with greater than 60-70% desirable cover will likely recover given proper fertility and rest. Stands with over 60% loss may require some renovation for full recovery. If pastures or hayfields have been thinned by drought, they can be reseeded by interseeding or frost seeding.
- Keep an eye out for additional weed pressure. When stands are weakened, there will most likely be increased weed competition and pressure from grassy and broadleaf weeds, and undesirable species may begin to fill in and take over. Pastures recovering from drought conditions are less able to compete with vigorous weeds, which can become more opportunistic and competitive. Be sure to scout and identify weeds that have not been encountered in the past and that may be toxic to livestock. Use concentrated grazing pressure, herbicides, or other weed management strategies to control them as needed.
- Fertilization can help speed recovery. Once moisture conditions improve, providing stands with adequate fertility can help speed up the recovery process by promoting additional forage growth and replenishing root reserves. Follow soil test recommendations to apply lime and other recommended nutrients to enhance plant survival and productivity. Remember that adequate soil pH can help enhance fertilizer uptake and efficiency, nitrogen can help stimulate growth, phosphorus is essential for root growth, and potassium is vital in helping plants withstand stressful conditions like drought.
- Delay harvest or grazing. New plant tissue for photosynthesis is limited during drought conditions; as a result, drought-stressed forages have used up a lot of their carbohydrate reserves and need additional time to recover. Treat drought-damaged pastures and hayfields like newly seeded fields. Once rainfall occurs and fields begin to green up again, allow time for top growth to accumulate and roots to regenerate before grazing or harvest. Grazing stressed pastures or harvesting stressed hayfields immediately after green-up will further weaken plants and lead to additional thinning, weed encroachment, and decline of stand condition.
- Maintain proper residual when harvesting or grazing. As always, maintaining an appropriate residual grazing or harvest height will preserve stored carbohydrate reserves and will shade and protect the soil surface. Avoid grazing or harvesting drought-stressed forages too short in the fall as they develop new tiller buds necessary for next spring’s forage production. A little extra residual will help with winter survival and quicker regrowth the following spring.
- Build forage diversity for added resiliency. Pastures and hayfields that include a diverse mixture of grasses, legumes, and forbs will often withstand drought (and other stressors) better than monocultures if some deep-rooted and drought-tolerant species are included. If you have not already, consider adding additional diversity to your forage stand. A dense plant canopy and root system will improve water infiltration and soil water-holding capacity by providing organic matter to absorb water and keep it in the root profile, helping to combat future drought conditions.
Obviously, there is no magical formula for dealing with drought conditions. Managing for drought is complex and must take place throughout the calendar year. Planning ahead and following good management practices can help see forage stands through dry conditions and not turn drought into a longer-term problem. While we can’t control how hot or dry summer will get, we can strategically manage the grass we have to help keep forages productive and protect stand integrity. Patience is critical, along with hopefully a little help from Mother Nature.