Spring Pastures and Drought: When do I turn out my Cows?

The question of when to turn out herds to spring pastures for grazing is an important one for all producers, especially those with dwindling hays or when purchasing feed. While drought planning is a routine part of most grazing plans, especially in Northern Alberta, many beef cattle herds have withstood successive years of drought prompting producers to make the best use of their pasture forage and carefully maintain carryover to avoid prolonged damage. 

Dr. Edward Bork, Professor of Rangeland Management at the University of Alberta, suggests that aside from spring rainfall, how your pastures looked when you brought cattle in last fall may be the best indicator of how they will perform in spring.

Reducing the Long-Term Impact of Drought

With higher feed costs it may be tempting for producers to turn their herds out to pasture sooner than they normally would, although it should be noted that this may cause potential long-term consequences, as when we stress forages we not only affect the above-ground growth but also the root system.

Deep roots require the most energy to maintain so they are the first to go, meaning that when they are not maintained the plant looses the ability to draw from deep soil moisture reserves. Deep roots store energy to keep plants active during a drought and are important for long-term survival. 

Dr. Bork recommends producers consider holding off turning cattle out if their pastures have been stressed recently. By managing pastures cautiously in the short-term, drought-related issues will not be at the forefront of concerns going forward. Avoiding long-term damage to plant health and root systems will help prevent erosion and even reduce a pasture's risk for weeds to establish.

Tips for Knowing when to use Spring Pastures

Know your Carrying Capacity

Develop your grazing plan with realistic expectations of the amount of forage you have available. Use regional range health guidelines of the Beef Cattle Research Council's Carrying Capacity Calculator to estimate the amount of forage available and how many animals the pasture can support.

Wait until the three-leaf stage

Using plant height is not a good way to determine readiness to graze as plants can vary greatly in the early stages. It is suggested to instead wait until plants have three leaves to start grazing, giving the plan enough time to build the reserves it needs for long-term survival. A common grazing rule of thumb is that for every one day you wait to graze in the spring you save two days in the fall.

Match your grazing plan to your pasture type

If possible, graze tame pastures prior to native pastures. Tame pastures tend to be more grazing tolerant and may be quicker to turn green in spring, providing valuable early grazing. In contrast, native grasslands often take long to reach peak production and should be deferred longer, if possible. 

Pay attention to litter

Litter is the dead plant residue left in a pasture. While litter serves multiple purposes in the prairies by conserving rain and snow melt it can also be part of the forage reserve. Pastures with abundant litter will require less recovery time and can be accessed earlier in the spring, compared to those with little or no litter. Grasslands without litter may produce 25-60% less forage than grasslands with adequate litter, as pastures with less litter lose moisture through evaporation and runoff and are at higher risk of sun and wind exposure.

Look backward

How was your forage managed in the previous year? If certain pastures were left in poor condition last fall, plan to use those later in the year to allow ample time for rest and recovery.

Use Rainfall rather than snow as an indicator

Looking at plants and pastures should always be the first indicator for forage growth potential, but many producers will also look to soil moisture levels to help determine pasture turnout. While snow can contribute to moisture it is not a certainty and it may have limited effect on recovery due to its tendency to evaporate or run off. Up to 70% of precipitation on the prairies comes from rainfall in the growing season as opposed to snow, meaning that our forage growth is closely tied to the occurrence of rainfall in May and June. Where soil moisture is severely depleted by drought the prior year, such as in much of Northern Alberta, spring growth will be even more dependent on timely rainfall.

Be ready to adapt

Recognizing that grazing plans made in early spring are a moving target and will need to adjusted based on rainfall, heat, and other environmental factors is key. Monitor pastures throughout the grazing season and consider potential back-up plans to ensure that pastures are managed for drought resilience.

Preventing Long-Term Damage to Pastures

If the drought conditions continue, pastures are going to require additional time to recover. It may be necessary to consider what steps you can take to prevent long-term damage now.

Consider alternative feeds, such as soybean hulls, beet pulp, pellets, screenings, or other feed sources that can be used to extend the winter feeding season or as supplements to pasture grazing.

Consider using annual forages to fill the gap, as these can be grazed for 4-6 weeks after seeding and can often be stocked heavily. This may help to alleviate pressure on grasslands, thereby allow them to reach their peak growth potential and get your grazing plan back on track.

Determine if destocking is necessary. While not an easy decision, it can help reduce reliance on stressed pastures and aid in faster recovery.

Consider shortening the breeding season and pulling bulls sooner means you are selecting for cattle that rebreed earlier, tightening up your calving season, and allowing you to take advantage of higher grasser market prices for open heifers. 

Managing pastures through drought is not an easy task, but planning ahead, monitoring, and being adaptable as the weather changes can help prepare your operation and prevent decline. Facing these challenges head-on better prepares producers for recovery and allows them to succeed when moisture is more readily available. 

Information in this article was sourced from the Beef Cattle Research Council https://www.beefresearch.ca/blog/managing-pastures-during-and-after-drought/