Every year I get a lot of calls about controlling weeds in fescue pastures and this year is no exception.
There are several things that can contribute to high weed populations in pastures. The obvious factor this year was all the rain that we got during the growing season. This stimulated more weed seed to germinate and, just like the grass they were competing with, it allowed them to get bigger faster. Other major contributing factors for weedy pastures includes poor fertility and over grazing.
Poor fertility is probably the leading cause of weedy pastures because poorly fertilized fescue tends to be thin and clumpy. This opens up the ground to more sunlight which stimulates weed germination.
The soil pH is quite important. When the pH goes below 6.0, the grass begins to thin out because of reduced tillering and reduced germination of new fescue seed. The pH can be corrected by adding two tons of lime per acre. This corrects the pH in the top inch or two of the soil. This will enhance fescue tillering and germination of new fescue seed in the bare areas.
In addition to pH, a shortage of phosphorous and potassium and low nitrogen levels can also lead to reduced tillering and reduced germination of new seed. Adding these nutrients will also enhance growth which makes the fescue more competitive.
If you do not regularly fertilize your fescue pasture, you should probably get a soil test to determine if you have a fertility problem and just exactly what that problem is. This test will allow you to take the action necessary as outlined above. You can bring the samples to our office. The test costs $6.50 apiece plus $5 postage for up to four samples.
Overgrazing is another factor that contributes to weedy pastures. Overgrazing isn’t just simply a function of having too many cattle in the pasture. It is a little more complicated than that. Specifically, the carrying capacity is dependent upon both environmental and fertility factors. Environmental variables includes seasonal rainfall, temperature fluctuations and soil type. Any one of these factors can lower the carrying capacity. Fertility factors are those that were explained above. However, it is important to realize that even the best pasture can be overgrazed simply by having to many cattle in the pasture.
Finally, weeds can be controlled through the use of herbicides. There are many herbicides that can be used that will do a pretty good job of controlling weeds in fescue pastures. A more critical factor is in the timing of this chemical application. Normally mid May to early June is the ideal time to spray fescue pasture. This is the time when most weeds have already germinated but are still small enough for good control. A drawback of using herbicides is the fact that desirable legumes may also be killed. So, in one respect, the quality of your pasture could actually be reduced if there are legumes that will be killed by the herbicide.
Give me a call at 724-8233 if you have questions about managing fescue pasture.
PITTSBURG —
