Grazing season is most commonly thought of as grazing during a period of time while the base forage is actively growing. This works great for producers who are seasonal in nature, such as stocker operators who grow winter annual pasture then completely utilize the pasture with stocker calves. However, for a cow-calf producer, thinking this way is very limiting to grazing management. For example, the figure below is the percentage of bermudagrass or nativegrass available for grazing during the growing season. Planned grazing during the growing season only limits grazing management options for the remainder of the year. Grazing managers should not limit their thinking to a season or period in time but rather expand their thinking to planning for multiple seasons and year-round grazing management.
As a grazing manager, success is tied to stocking rate or the number of animals grazing an area of land for a period of time. As mentioned previously, cow-calf producers should think of the period of time as a year. Note in Figure 1 that the majority (70 percent) of bermudagrass and nativegrass growth occurs prior to mid-July. This means the amount of forage available for grazing is greatest in spring and early summer. Animal performance is directly tied to forage availability; therefore, animal performance should also be greatest in spring and early summer. For a spring-calving cow herd, it is time for the cow to maximize milk production, add body condition and rebreed. If stocking rate is set too high in an attempt to utilize all of the abundant seasonal spring growth, then there is risk of limiting forage intake and cow performance due to restricting forage availability. Other risks include reducing total forage yield, possibly reducing plant persistence, and increasing cow carrying costs due to increased supplementation from reduced forage availability the remainder of the year.
For long-term sustainability of both the livestock and the forage base, set a stocking rate based on a time period of a year and the amount of forage the operation can produce in a normal rainfall year. Excess forage will likely be available during the spring, but that can be utilized later in the year. Combine this with a controlled rotational grazing plan. Rotational grazing presents additional forage management options such as allowing for stockpiling forage for fall grazing. Grazing intensity and duration can also be controlled through rotational grazing. Highly productive pastures can be grazed harder, and weaker pastures can be given an opportunity to rest and recover. A side benefit to rotational grazing is that over time, the cow herd will become easier to handle and work.
Preparation is key for making a year-long grazing system work. The grazing manager needs to be thinking at least one season ahead and maybe two. Learn the yearly flow of both perennial and annual forages. Take into account rainfall that is received in one season and how that will affect forage production in the next season. In summary, be flexible, proactive and have a mindset of year-long forage flow in addition to solely seasonal grazing.