Many livestock producers, specifically, beef and dairy producers, like to graze cattle well into the autumn months. In fact, in a year like this, where we have some good weather well into November, without any snow cover, we can go up to Thanksgiving or later. The more we can get from our pastures, the longer we can wait to tap our forage supplies that are in the barn or in the silos. Good hay is expensive and the temptation is to leave cattle out on pasture as long as possible to conserve what we do have.
The problem with this management is that we can overgraze our pastures and adversely affect next years pasture production. We have had two consecutive years of dry summers that may have compromised some of our perennial pasture plants by not allowing them enough time to recover from grazing pressure.
Grazed pasture plants start to regrow in about 3-5 days. Livestock prefer the tender new shoots of plant regrowth vs. the mature growth of plants going to seed. When you overgraze pasture, you allow livestock to continue eating the new regrowth, causing the plants to use up energy stored in the roots. Plants need leaf area to enable photosynthesis to produce stored energy for regrowth. Overgrazed plants do not have adequate leaf area for photosynthesis to take place
What will pasture overgrazing in the fall cost you next spring as plants start to grow?
Overgrazed pastures have not had a chance to mature enough to store the energy reserves needed to power regrowth next spring.
Overgrazed pastures are slow to grow in the spring, thus costing you pasture growth and tonnage the next year. Also any perennial pasture legumes may not come back at all if grazed continuously the previous fall.
We recommend that alfalfa should not be harvested after September 1st to ensure enough regrowth to survive through the winter. Most pastures have some alfalfa or white clover as part of the pasture mix. A few years of overgrazing and these plants will disappear.
When desirable plants disappear, the opportunity exists for weeds to move in and take over. Rotational grazing management, where pastures are given rest periods and allowed to regrow and put down root reserves, is the bets management strategy. This allows the desired plants time to thrive and compete with weeds.
So what are some management practices that can help an overgrazed pasture to recover and become productive again?
All plants need proper nutrition to thrive and grow. Take soil samples of your pasture and fertilize accordingly. Allow the pasture plants time to grow to the proper height to allow photosynthesis to occur and thus meet the energy needs of the plant both for regrowth and root reserves before beginning to use the pasture again next spring.
Remember that what you have on top of the soil for plant height is about the same as you have below the soil for a root system.
Overgrazed short plants do not have much of a root system. The taller plants in a pasture grazing mix typically have a very extensive root system that is needed to take in the nutrients and water needed to support the plant during the whole year.
When you think about it, plants only have a six month window to put up enough nutrients to last all year long. By constantly removing the top growth, the plant can weaken over time and finally starve to death after its root stocks are exhausted.
Overgrazing can affect survival rates of perennial plants in the pasture mix. Through proper management, you can ensure years of productive growth and avoid having to start over.