Do you have pastures you want to renovate and improve, or do you have new pastures or hay fields you want to establish next spring? If your answer is “yes,” then now is the time to begin action. Don’t wait until late winter or next spring to begin preparations.
There are several things you need to do yet this autumn to have success with pasture improvement, renovation, and good establishment of new forage seedings next spring.
These include soil testing and applying lime and fertilizer and weed control. Where you plan to renovate an existing pasture by adding legumes, you will also need to weaken the existing sod so it is less competitive.
Soil testing
Begin by collecting soil samples as soon as possible. Send samples to a reputable lab. Contact your extension office for useful resources to guide you in this process, such as how to take a good soil sample, where to send the sample, and how to interpret the test results.
For example, Ohio State University provides a series of factsheets to guide you in soil sampling and testing, which are all online at http://agcrops.osu.edu/specialists/fertility/fertility-fact-sheets-and-bulletins.
If you plan to renovate a pasture or make a new no-till seeding, you should consider collecting samples at two depths. Take samples at the normal 8-inch depth for nutrient availability and separate samples at a 2-inch depth to check soil pH for lime recommendations.
After you get the results back, be sure to check the recommendations against university guidelines for your region. Don’t assume the recommendations on the report are the same as those recommended by the university in your region.
I have seen recommendations that are way out of line with university guidelines. We need to base our fertility program on data and proven responses, for both economic and environmental quality reasons.
Apply lime and fertilizer. It is critical to take soil samples this fall, especially so you can apply lime if the soil pH is low. Soil pH is not changed overnight, and lime acts slowly to neutralize soil acidity. So apply needed lime this fall as soon as possible where needed. Low soil pH will reduce the plant availability of many nutrients, including soil nitrogen, phosphorus, potassium, calcium, sulfur, magnesium and molybdenum.
Soil pH should be above 6.0 for most forage species, and above 6.5 for alfalfa. Apply other nutrients needed this fall, based on the soil test. For example, phosphorus is very important to root growth and legume survival and potassium helps with yield and winterhardiness.
Soil pH correction and applying needed fertilizer goes a long way toward improving the existing pasture and making it more competitive with weeds over time.
Control problem weeds
Fall is the best time of the year to control many problem weeds with herbicides. Most weeds are much more difficult to control in the spring. In the fall, perennial weeds are storing energy reserves in the root system, so herbicides are translocated downward into the root system.
If the chemical does not completely kill the plant this fall, it will often die over the winter from the herbicide stress. For herbicides to work effectively, they should be applied when the weeds are in an advanced stage of growth but still actively growing and when temperatures are relatively warm.
So herbicides should be applied soon to weeds in advanced stages of growth, especially if the weeds are warm-season perennials, such as common pokeweed and horsenettle. Herbicide applications will still be effective later into October for cool-season perennial weeds like thistles, dock, dandelion and smooth bedstraw, among others examples.
But warm-season perennials will shut down with the first frost and herbicides won’t be effective. You should develop a weed control strategy to manage problem weeds over time. Realize that it is very difficult to eliminate perennial weeds with a single herbicide application.
But this fall is a good time to start a control program, especially if you are planning new seedings or pasture renovations next spring. Also keep in mind that most herbicides that control perennial weeds will kill the legumes in your pastures.
So a chemical weed control program should be followed by frost seeding or no-tilling legumes back into the stand. Helpful resources to help you develop a weed management strategy are available online at http://agcrops.osu.edu/specialists/weeds.
The Ohio and Indiana Weed Control Guide is an excellent resource to begin with, available at Ohio State University Extension Offices or online at the above link. Another excellent resource is the Penn State University Weed Management in Pasture Systems, available at http://extension.psu.edu/pests/weeds/control/weed-management-in-pasture-systems.
This publication also discusses all aspects of a good weed control program, including cultural controls, which are especially useful for organic systems or for those not wanting to use herbicides.
Weaken the sod prior to renovation. Weakening your sod may seem counterproductive and exactly not what you want, but in fact it is required to successfully add new species to an existing sod. Competition from the existing sod is the single-most detrimental factor in establishing legume seedlings into an established sod.
You need to severely weaken the existing sod this autumn in order for legume frost seeding or no-till drilling of new forage species to be successful next spring.
How do you accomplish this? By extreme overgrazing!
Yes, you need to graze the existing sod into the ground this fall … and I mean literally into the ground. This will weaken the sod so that next spring it grows very slowly, which allows the seed you sow to germinate and establish before the existing sod resumes vigorous growth.
Start with a small area and see how it works if you have never done this before. If you need to apply herbicides to control weeds, do that first, but be sure to observe the waiting period on the herbicide label before grazing.
Then graze the pasture down hard before the winter. If the pasture grows back a little this fall, graze it hard again. After nothing is left, graze it a little longer. In late winter, while the ground is still freezing and thawing, broadcast clover seed to the pasture.
As the pasture begins to grow next spring, graze it just enough to keep the grasses from shading out the new legume seedlings underneath. Graze only when soils are relatively firm to avoid damaging the new seedlings.
Spring success
This autumn follow these steps of soil testing, applying needed lime and fertilizer, controlling perennial weeds, and suppressing the existing sod. Doing so will place you in a much better position for successful results next spring when you take additional steps to renovate old pastures or establish new stands.
Excellent article.
Be careful grazing too much in the fall, you might get a good legume establishment early in the spring, however if you do what this guy is recommending, you will most likely do more harm to your current pastures than good. If you overgraze a plant while it is still growing, then re-graze that same plant soon thereafter, you will deplete that plant’s nutrient stores to the point that you could actually kill it. What I would do (and have done with success) is let the fall forage stockpile, wait until it goes totally dormant, THEN graze it hard (IE like late December), preferably when the ground is frozen so your critters don’t pug the ground up too bad. There is still plenty of green under the brown to keep them interested, they’ll eat it. Then, in late Feb. or early Mar., frost-seed your legume. Then when the spring growth starts, leave it ALONE. The clover will be overshadowed at first by the grass flush in the spring, but clover seed (and most legume seeds) are tough, they will hang in there. By mid summer you will notice the the clover starting to come in and by fall you should see good establishment.