Alfalfa (Medicago sativa) is an important perennial forage crop used around the world. Roundup Ready alfalfa should also be removed by similar methods. Crop protection companies are suggesting how growers of the herbicide-tolerant alfalfa can manage the new crop’s weed control program. In the Northeast, alfalfa is often seeded with a grass in a mixed stand. In a small area that hadn’t been sprayed, alfalfa was 8–12 inches taller than where glyphosate had been applied. potential in the following years. Table compares the relative effectiveness of herbicides on individual weeds. With the broadest application timing window plus excellent crop safety, Roundup Ready Alfalfa requires minimal waiting — only 5 days before grazing or harvest. Results may differ with variation in weed size, temperature, rainfall, soil moisture, soil type, and soil pH. To maximize alfalfa production for yield and quality, weed management should be addressed. Hoffman. Alfalfa is the fourth largest crop, in terms of acreage, grown in the United States behind corn, soybeans, and wheat. Follow label guidelines.2 Herbicide should be applied to alfalfa with at least 10 inches of spring growth or after 6 inches of alfalfa regrowth. Companion crops reduce stand loss due to wind and water erosion and may suppress growth of some weeds. Roundup Ready Alfalfa seed or crops (including hay and hay products) to China. By: Keef. Weed competition during establishment will reduce alfalfa seedling vigor and potentially reduce the alfalfa plant population, which can affect crop yield and quality throughout the life of the stand. Read the thread about RR corn. Second applications. Rate: Up to 44 oz/A Roundup Original Max or WeatherMax in a single application, not to exceed a total 132 oz/A for in-crop treatments per year . glyphosate application is necessary at the 3 to 5 trifoliate leaf stage to remove the small percentage of glyphosate-susceptible alfalfa plants that can be present in a new seeding (and to kill any weeds present in the stand). A South Dakota alfalfa seed grower who filed suit when Roundup Ready alfalfa was released in 2005 remains in a legal battle against its parent company. Ratings are based on labeled application rates and alfalfa size or growth stage. Increased, High-Quality Yield Opportunity Roundup Ready Alfalfa can deliver a higher percentage of pure alfalfa in hay and haylage than competitors, along with improved quality. 1 Only 2,4-D may be applied prior to soybean planting. By entering your email, you consent to receive communications from Penn State Extension. Therefore, with alfalfa, management practices will not only affect the first harvest of the crop, but will also affect subsequent harvests within the life of the alfalfa stand. Loading... Unsubscribe from AFGC ORG? Alfalfa seedlings establish slowly and are very sensitive to competition for limited resources. Roundup Ready (RR) alfalfa is a popular weed management strategy for alfalfa producers in California and other western states, with the greatest advantages considered to be excellent weed control without crop injury. If the alfalfa isn’t a Roundup Ready variety, glyphosate can be applied 36 hours or longer before harvesting. Glyphosate resistance management should always be implemented when using glyphosate-resistant crops, such as Roundup Ready alfalfa. Ratings were collected from trials conducted in Pennsylvania or neighboring states. In addition, successful weed seed production during alfalfa establishment will potentially increase weed seed reserves in the soil, contributing to future infestations. Once alfalfa is established and is successfully into the forage production period (after the first harvest), well managed alfalfa stands are generally vigorous and aggressive enough to compete well with later emerging weeds. Evaluating alfalfa stands 30-40 days after planting is an eye opening experience for many. Always start with a weed-free field. Table compares the relative effectiveness of herbicides for control of Roundup Ready alfalfa. For spring seedings in the Midwest, companion crops also … In addition, due to the unique cropping practices do not plant Genuity Roundup Ready Alfalfa in Imperial County, California, pending import approval in China and until Monsanto grants expressed permission for such planting. Preliminary research has shown that it is possible to attain good weed control in mixed alfalfa-grass stands using glyphosate and Roundup Ready alfalfa, but strict management guidelines must be followed. Up to 10 percent of the Roundup Ready alfalfa seedlings may not be resistant to glyphosate due to the genetic diversity of alfalfa; these susceptible plants are referred to as "nulls." When I replanted, I went through most of the entire field. Add AMS at 8.5 to 17 lb/100 gallons of spray solution. Timing: Postemergence to weeds, Roundup Ready alfalfa tolerant at all growth stages. Greater than 95% control can be achieved with a combination of 2,4-D and dicamba without tillage when used prior to no-till corn. Roundup Ready® (GENRR) alfalfa, which enables growers to apply glyphosate agricultural herbicides up to 5 days before cutting for unsurpassed weed control with excellent crop safety. In 1996, genetically modified Roundup Ready soybeans resistant to Roundup became commercially available, followed by Roundup Ready corn in 1998. ROUNDUP READY ALFALFA - ESTABLISHED STANDS (NON-SEEDING YEAR) General Information PRODUCT INFORMATION Product Description: This product is a postemergence, systemic herbicide with no soil residual activity. Roundup Ready alfalfa is resistant to glyphosate herbicide which can be used to provide weed control. oz 3S formulations, Remove livestock before application and wait a minimum of 5 days after application before grazing, or cutting and feeding forage or hay, After the first cutting, apply up to 5 days prior to harvest. If necessary, the spring application should be made when weeds are actively growing but less than 4 inches tall. 1973. Spraying at the 3 to 5 leaf stage insures that all alfalfa seedings have emerged. Did any drift occur? If your alfalfa variety is Roundup Ready, you can spray almost any time without hurting your alfalfa. If an appropriate glyphosate application is not made early in the life of the alfalfa stand, such as the recommended 3 to 5 trifoliate application, later applications will control the susceptible nulls leaving gaps or holes in the canopy of the alfalfa. EPSP synthase is present in most plants and is an enzyme essential for protein synthesis and normal plant growth. Spray Weeds Early with Roundup Ready Alfalfa By Bruce Anderson Extension Forage Specialist University of Nebraska–Lincoln If you planted Roundup Ready® alfalfa this spring, it may be time for that first herbicide application. Spraying at the 3 to 5 leaf stage insures that all alfalfa seedings have emerged. However, when glyphosate is applied to seedling alfalfa, the removal of the nulls has no impact on the future production of the stand. It is generally non-selective and gives broad-spectrum control of many annual and perennial weeds, woody brush, trees and vines. If the glyphosate application is made after the 3 to 5 trifoliate stage, some yield loss may occur due to the competitive effects of the weed on the crop; in other words, the damage has already been done. Roundup Ready technology has been successfully incorporated into alfalfa and is scheduled for commercial release in 2005. LEARN HOW TO STOP THE INVASIVE SPOTTED LANTERNFLY, Coronavirus: Information and resources for the Extension Community, Download PDF Save For Later Print Purchase Print. Roundup Ready Alfalfa has demonstrated it makes late summer seeding of alfalfa a great option. At Penn State, glyphosate was used for weed control during early establishment of Roundup Ready alfalfa, while the grass was seeded after herbicide application (4 to 5 weeks after seeding alfalfa). We also saw some benefit in 2011 to using roundup ready varieties when field conditions forced late plantings of the alfalfa. When glyphosate is applied to susceptible plants, glyphosate blocks EPSP synthase preventing the production of essential amino acids and the plant dies. To maximize the benefits of Roundup Ready alfalfa, glyphosate should be applied to seedling alfalfa at the 3 to 5 trifoliate stage when weeds are less than 4 inches tall. Roundup did and excellent job of controlling the different populations of weeds that occurred with the late plantings. Kuehn, C.S., H.G. The alfalfa crop will remain in the field for several growing seasons and will be harvested several times each season. The rest is about 6 inches tall. Although Roundup Ready alfalfa can be an excellent option for weed control in alfalfa, it may not be appropriate for all situations. Glyphosate should only be applied when conditions warrant weed control as to reduce the potential development of glyphosate-resistant weeds. Traditionally, oats Do not use dicamba prior to planting soybean or other susceptible crops. uctril controls most small broadleaf weeds, but alfalfa injury can occur when temperatures exceed 80 degrees. The effectiveness of glyphosate and other herbicides on common alfalfa weeds are described in Table 1. Planted the first time in Aug of 13 and the second time about May 5th. On Farm Observations. If weed problems persist, an additional application of glyphosate can be made up to 5 days prior to harvest. Roundup Ready alfalfa removal prior to crop rotation is similar to conventional alfalfa varieties. Vol is correct about weed control in Roundup Ready alfalfa using 22 oz. Roundup Ready alfalfa can be planted in the spring or late summer using standard alfalfa establishment practices. During the last month I have had several calls about the proper timing to spray Roundup Ready alfalfa varieties with Roundup. However, in plants that are Roundup Ready, a modified EPSP synthase is unaffected by glyphosate and allows the plant to continue growing. Roundup Ready alfalfa may also help in the establishment of no-till alfalfa stands; however, additional research is still needed on effectively using no-till in Roundup Ready alfalfa. Fields with perennial weed problems may also be good candidates. And spray Roundup before weeds and alfalfa seedlings get more than about three inches tall. Weeds and alfalfa hay quality. Roundup Ready alfalfa can provide high quality, weed-free forage with excellent crop safety and minimal harvest restrictions. Jung, J.G. If weed problems persist after the initial application, a second application of glyphosate may be applied up to 5 days prior to first harvest. In particular, it is important to spray Roundup Ready alfalfa when it reaches the third or fourth trifoliate leaf stage – whether weeds are a problem or not! A second reason for glyphosate application at this time is to control the alfalfa "nulls." Applying glyphosate prior to the 3 to 5 trifoliate stage may be too early for effective weed control since many of the weeds have not emerged by this time (depending on seeding date). If it does get late and alfalfa turns green before you can spray, switch your herbicide choice to either Pursuit or Raptor. If properly planned, Roundup Ready alfalfa is no more difficult to remove than conventional alfalfa varieties. Linn, and N.P. But if weeds are present at earlier stages of alfalfa growth Roundup can be sprayed on … Late summer seedings may have glyphosate applied in the fall or spring to control weeds. “One of the greatest benefits of this type of alfalfa is that growers can spray in between cuttings to control annual weeds and grass,” says Benyshek. When corn is 30 to 48 inches tall, only use drop nozzles and avoid spraying into the … In particular, alfalfa-grass mixtures and alfalfa seeded with companion or nurse crops are generally not suitable. of Glyphosate/acre. into the alfalfa plant. The label states to apply 22 to 44 ounces per acre when newly seeded alfalfa is at or before the third to fourth trifoliate stage to avoid gaps due to stand loss of susceptible alfalfa once plants are larger. Prepared by Bryan L. Dillehay, Ph.D. candidate, and William S. Curran, professor of weed science. If weed problems persist, an additional application of glyphosate can be made up to 5 days prior to harvest. When considering the value of this technology, the Royalty fee should be amortized over the life of the stand and the value of glyphosate herbicide should be compared to other competitive products. Alfalfa is also used for greenchop and silage in many areas. The sun will help the vinegar dry out and kill them. The same thing occurred in several other fields that spring. Renz outlines several options for this scenario. ... Making Your Alfalfa Better #791 (Air Date 6/2/13) - Duration: 6:35. You can mix 44 oz of Glyphosate in your 26 gallon spray tank and use a surfactant if you desire, but it is not necessary. Fortunately, if you treat your alfalfa as soon as possible during upcoming spring-like weather, you can have cleaner, healthier alfalfa at first cutting. for Roundup Ready® Alfalfa Seed Production IntRoductIon The genetic supplier members (hereinafter called the “Companies”) of National Alfalfa & Forage Alliance (NAFA) have agreed to jointly adopt, as a minimum, the following Best Management Practices for Roundup Ready Alfalfa (RRA) Seed Production in the United States. Ratings are based on labeled application rates and weed size or growth stage. Alfalfa forage composition as affected by weeds can have significant impacts on protein content and overall feed quality (Cords 1973). 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