As we progress through October, producers need to be thinking about their grazing exit strategy. By now, you should have finished your last hay harvests and made any soil fertility applications in anticipation of fall dormancy.
Our cool-season grass species have passed the peak of the late summer/early fall growth period and are slowing down their vegetative growth rates.
The question of when to end the grazing season is not determined by the calendar, but more a question of the current conditions, your forage needs and your management plans for the remainder of the fall and into next spring.
Stored energy
To start the discussion, we need to think about what our grasses would be doing if we didn’t need to harvest them or have our livestock harvest them for us.
The decreasing day length and cooler temperature are signaling to the grasses and legumes that winter is approaching, and they need to be storing energy prior to winter dormancy.
This stored energy will be important to initiate regrowth next spring.
If the plant is not given the opportunity to store energy and produce sufficient above-ground leaf mass to provide insulation, it may not survive the cold of winter and will struggle to get going next spring. Where this energy is stored in the plant is dependent on the species.
Tall fescue and orchardgrass store carbohydrates in the lower stem and crown. Timothy stores sugars in basal internodes at the base of the plant. Kentucky Bluegrass and legumes store energy in the crown and root system.
I hope that you have picked up that all of our cool-season species store their energy reserves in the lower part of the plant and/or in their root system.
If we stress the plant late in the growing season, it may use up a large portion of its energy to regrow and not have time before dormancy to replace those reserves.
When to end
So, when should we wrap up our grazing at the end of the year? As I mentioned, there are a couple of decisions to make, and all are related in some way to what you need for next spring.
Ideally, your last pass through each paddock is completed in a way that minimizes soil disturbance from your livestock’s hooves and leaves behind 3 to 6 inches of top growth.
When final grazing height is in the 3-to-6-inch range, there is sufficient leaf area for photosynthesis to occur, which allows for plant regrowth and the continuation of carbohydrate storage without depleting plant energy stores. Ensuring the minimum above-ground mass will provide insulation to the plant and protect the soil by limiting potential erosion.
The last two years have prevented producers from storing the amount of hay they would like, and many will be encouraged to take advantage of pasture availability as long as possible. You just need to be aware of the potential consequences.
Short grazing in the fall can be a benefit if you plan to frost seed or renovate next spring. By grazing close now, there will be less vegetative mass in the early spring, which will help promote seed-to-soil contact for those broadcast applications and make no-till planting easier once soil temperatures allow planting.
If you will be grazing these pastures next spring, you will need to look at your rotation plans.
Those paddocks that are stressed this time of year will be slower to get started next spring. They will not be the ones that you should plan to graze first in the spring to give them extra time to get going.
The grass can stop growing at any time as we approach early November. Some areas may have already had a killing frost in low-lying areas.
Options
If you want to hold off on feeding hay as long as possible, you do have a couple options. First off, you can continue through your rotation.
Those pastures that have regrown can continue to be grazed. You may need to shorten the time on those paddocks and/or alter your stocking density so that the animals are pulled when you reach that 3-to-6-inch final height.
I would caution those who struggled last year with the drought may want to be extra cautious this year to help keep those pasture grasses recovering. Once the grass has run out, you can look to alternative forage options. If you planned ahead, you could begin grazing winter annual crops.
Most regions have begun corn harvest, and residues will be available for strip grazing. Stockpiled grasses should not be grazed until after a killing frost, so as not to run into the same problems as overgrazing your other pastures in the fall.
