Tag Archives: burndown of cover crops

Annual Ryegrass Forage Story from Southern Canada

From the Canadian Cattleman magazine, a story from Alberta about a cattleman with an eye for steer health and profits. Click here for the whole article.

Andy Schuepbach, a registered Hereford breeder in southern Alberta, uses two varieties of ryegrass to provide fall and winter feed for his cattle. The high protein content of these grasses eliminates the need for any other protein source.

“We grow barley for silage, and after it’s seeded we seed 10 pounds of a mixture of Italian ryegrass and annual ryegrass. The Italian ryegrass has phenomenal feed value. We bale a little for our calves but use most of it for winter grazing,” he says.

The Italian ryegrass has fine leaves and is very palatable so young calves do well on it. Calves won’t eat coarse feed, and this grass is very soft. “We calve in February and March, and always struggle with ulcers in the calves. We have a lot of windbreaks and open-face sheds with bars across, halfway back, so the calves can get into the back part. This is where we set up a round bale with panels around it. The calves can eat the bale through the panel bars,” he explains.

Annual Ryegrass – Manage it Properly

Managing annual ryegrass is not rocket science…but it is all about science. Therefore, being precise about the process of killing the cover crop is important.

In prior posts, you’ve learned about the timing, the weather, the proper mix of glyphosate, adding AMS and balancing the water hardness with citric acid if needed. Some add a surfactant and even 2,4-D for better control and to get rid of other broadleaf weeds at the same time.

By now, you may have seen already whether one full-rate application of glyphosate was enough. Inspecting the field a week after the first application is smart. Look closely. Any sign of green warrants another application.

After your corn or soybean crop emerges, you can control any annual ryegrass escapes with a labeled rate of Accent Q, Steadfast Q, or Option, but best control is obtained with these products when temperatures are above 70 degrees.

For more information, check out the website or download a comprehensive four-page brochure.

Killing Annual Ryegrass – Part 2

Annual ryegrass is a vigorous plant. Planted last summer or fall, the roots can be established to more than 5 feet into the soil. So, even if there’s only 6 – 8 inches of top growth, treat annual ryegrass as a mature plant. Successful control of annual ryegrass with glyphosate or other herbicides depends on:

Using full herbicide rates
Spraying during favorable weather conditions
Using good spraying practices.

Click here for a free brochure: Annual Ryegrass Management

Click here to go to the Annual Ryegrass website, for more detail on management.

Controlling annual ryegrass in the spring is best done:

In warm weather
When the ryegrass is actively growing.

Annual ryegrass can be a challenge to control if the herbicide is applied when:

There is cool, cloudy and wet weather, or
When the ryegrass has reached the joint growth stage (stem elongation).

Timing – Control (burndown) of the annual ryegrass cover crop:

Is most successful when the plant is small, 4-8” in height
Annual ryegrass is more difficult to control after the first node has developed
Burndown occurs before the middle of April

Killing Annual Ryegrass – Be Precise for Success

At every trade show and field day, we hear the story (thankfully, fewer times each year) about how “hard it is to kill annual ryegrass.” Invariably, when you ask a couple of specific questions, the problem becomes very clear. “In some things about agriculture, you can cut corners and not cause too many problems,” said Dan Towery. “With annual ryegrass, you’re asking for trouble if you deviate from a strict management protocol.”

So, the first question Dan asks people who have trouble with annual ryegrass management:

Did you add AMS (ammonium sulfate) to the tank water and agitate it BEFORE adding the glyphosate?

Ammonium sulfate is a surfactant, whose purpose is to improve retention on the leaf surface and increase movement of the herbicide from the leaf surface into the leaf. AMS also softens “hard” water, helping to nullify the impact of naturally-occurring magnesium and calcium.

WIthout AMS, the minerals in water will compromise the effectiveness of glyphosate.Adding AMS helps the translocation of glyphosate to the annual ryegrass.

What time of day was the glyphosate sprayed on the annual ryegrass cover crop?

Proper translocation of glyphosate into the plant tissue depends on the air temperature, the weather and what time of day you apply it. For more specific information on this particular aspect, click here to take you to the annual ryegrass website.

Managing Annual Ryegrass this Spring

Controlling annual ryegrass in the spring with glyphosate or other herbicides depends on: (click here for the larger, more detailed version)

Using full herbicide rates
Spraying during favorable weather conditions
Using good spraying practices.

Controlling annual ryegrass in the spring is best done:

In warm weather
When the ryegrass is actively growing.

Annual ryegrass can be a challenge to control if the herbicide is applied when:

There is cool, cloudy and wet weather, or
When the ryegrass has reached the joint growth stage (stem elongation).

The next post will have more specific guidelines. In the meantime, check out the Annual Ryegrass website for more detailed infomation.

Seeding Rate for Annual Ryegrass Cover Crop Varies

In past years, we’ve published pretty standardized rates for seeding annual ryegrass into corn and soybeans. The rates vary from about 12 llb/ac (drilling) to 25 lb/ac if broadcast or aerial seeding. Click here to go to our four-page management guide or here for our handy Quick guide.

Now, even among experts, there’s some thought to lowering the recommended seeding rate, in order to save money but also to make it easier to manage the ryegrass in the field.

Mike Plumer has seen instances where annual ryegrass was too heavy, creating difficulty drilling into it after burndown. The root mat of annual ryegrass, if too dense, can complicate the closing of the seed trench. Further, he says that annual ryegrass roots seem to go deeper if the stand is thinner, because the plants don’t have as much competition with each other. He’s seen effective stands at as low as 8 lb/ac and thinks the 25 lb/ac is too heavy.

Dan Towery is more cautious about cutting back on the recommended seeding rate. While he agreed with Mike that certain growing conditions would warrant less seed/ac, he doesn’t want to end up with stands that are too thin. He said that the 2012/2013 cover crop season was unusual in that annual ryegrass did super well. The reasons: lots of residual N in the field from last year’s drought, September rain that got the ryegrass established well and a long spring that prolonged the cover crop season.

The consensus decision, after more discussion, will manifest in a modification of language in our brochures. Stay tuned…but it looks like growers will be advised to use best practices for your area and the climate conditions. That means asking the experts, whether at your seed supplier, your Extention agronomist….or your neighbor who’s been growing successful cover crops and can guide you on the local recommendations.

And then again, you can always contact us…we’ll put you in touch with Mike or Dan – or any number of other successful cover crop growers in your area – and you can hear it directly from them..

New Annual Ryegrass Publications

The Oregon Ryegrass Commission has published three helpful new flyers to aid in your selection and management of annual ryegrass as a cover crop.

1. Selection of Annual Ryegrass

2. 2014 Annual Ryegrass Management Guide – “Quick” 2-pager

3. 2013 Annual Ryegrass Management Guide – Comprehensive 4-pager

Please let us know if these could use further information or clarification.

All of these and more are available on the Annual Ryegrass Cover Crop website.

Burndown Advice for Annual Ryegrass

Now’s the Time to Begin to Take Out Your Annual Ryegrass Cover Crop
1. Timing is important. Late March – Mid April, depending on Midwest location
a. Burndown when the plant is 6 – 12”, before 1st node develops
b. Allow 5 – 7 days after annual ryegrass has begun to actively grow before spraying

2. Temperature is crucial. Should be above 60° F
a. Spray on a sunny day if possible
b. Wait a few days if nighttime temps dip below 38°F
c. Soil temperature should be above 45°F
d. Stop spraying about 4 hours before sunset to allow for max. translocation within the plant.

3. Coverage. Be thorough, use medium spray droplet and moderate pressure
a. Use flat fan nozzles, at 30 – 40 psi
b. Don’t use air induction nozzles that produce a course droplet size.

4. Primary application. One application of glyphosate may be enough for burndown
a. However, plan for two applications, using herbicide with a different mode of action
b. Scout the fields afterwards to ensure annual ryegrass is dead (it may look brown but can grow back)
c. Glyphosate use. Apply at 1.25 – 1.5 lb. a.e./a
d. Add ammonium sulfate and a surfactant
e. Adjust pH and follow mixing directions on the label carefully
f. When using additives, mix them first for 3 – 5 minutes in a full tank of water, before adding the glyphosate; water should be free of clay particles.

5. Precautions, and other herbicides to use when planting corn
a. Never mix atrazine or Callisto with glyphosate (ryegrass control will diminish)
b. Adding 1lb a.e./a Princep (simazine) improves weed control (not in sandy soil)
c. Use of Balance Pro, Prowl H2O, Resolve Q or Basis Blend, 2,4-D, Axiom at full label rate for residual weed control.

6. Use of other herbicides when planting soybeans
a. After beans emerge, annual ryegrass escapes can be controlled with full rates of SelectMax, Poast Plus or Fusilade DX.
b. Use fertilizer, surfactant, crop oil as label-directed. Less effective in cold temps.

Annual Ryegrass and Nitrogen Uptake

A recent article by Farm Journal writer Darrel Smith, talked about a nitrogen study with different cover crops, and the importance in managing the burn down so as to maximize nitrogen uptake by corn and beans.

Farm Progress worked with Dan Towery and Ken Ferrie on the project. The following paragraphs are from the article. To read the entire article, click above on the Farm Journal highlight.

“Annual ryegrass is a nitrogen scavenger, and has a relatively low C/N ratio—as low as 17/1 if you burn it down early,” Towery says. “Because the annual ryegrass was planted into wheat stubble, it may not have taken up much nitrogen because there wasn’t much in the soil to begin with—possibly less than 20 lb. per acre. I’ve seen annual ryegrass take up much more nitrogen than that—90 lb. to 120 lb. per acre, depending on field history.

“The low C/N ratio of annual ryegrass means that typically 50% to 75% of that nitrogen becomes available to corn plants six to 10 weeks after it is killed in the spring—in late June or early July,” Towery continues. “Often, corn fields following an annual ryegrass cover will be dark green, or even almost black in July. That has to be from the nitrogen mineralized from the annual ryegrass, and the absence of a carbon penalty, resulting from the crop’s low C/N ratio.

Annual Ryegrass Control – Tips for Qualtity Results with Herbicide

3. Coverage. Be thorough, use medium spray droplet and moderate pressure
a. Use flat fan nozzles, at 30 – 40 psi
b. Don’t use air induction nozzles that produce a course droplet size.