University of FloridaSolutions for Your Life

Download PDF
Publication #SS-AGR-261

Weed Control in Perennial Peanut1

Jason Ferrell and Brent Sellers2

Introduction

Perennial peanut has been called “Florida alfalfa” because it is a high-quality forage legume that performs well in tropical climates of the Deep South. Perennial peanut is highly palatable to most livestock, and bloating is not a problem as it is with many legumes. For these reasons, perennial peanut has filled a niche in the high-quality legume hay market.

In the past, weed control has been a difficult issue to overcome with this crop because very few herbicides could be used. Recently, the Florida Department of Agriculture and Consumer Services concluded that the following expanded list of herbicides can be used on perennial peanuts. However, it must be noted that this is a Florida ruling. Producers in Alabama, Georgia, or other states must check with their local regulatory agencies to ensure that these products can be used in their states.

After numerous field trials, we have compiled the herbicides that can be applied to perennial peanut without risk of adverse effects. This list contains very few products, but if used properly they should improve control of some troublesome weed species.

Tables

Table 1. 

Recommended herbicides for perennial peanuts.

Trade name and broadcast rate/A

Common name

Remarks

2,4-D amine Weed Killer

(EPA 1386-43-72693)

(1 pt/A)

2,4-D

(0.5 lb)

For control of many annual broadleaf species such as Mexican tea (Jerusalem oak), pigweeds, Spanish needle, etc. Can be applied any time during the season as long as the 30-day restriction on hay cutting is observed. May lead to slight yield decrease in 'Florigraze', but 'Arbrook' is more tolerant. Mixing 8 fl. oz of 2,4-D amine Weed Killer with 4 fl. oz of Impose has been found to be an effective combination.

2,4-D amine Weed Killer is the product that has been officially approved for use. Take care to use this particular product rather than other non-approved 2,4-D herbicides.

Impose

4 fl. oz/A

imazapic

Impose is highly effective on crabgrass, nutsedges, johnsongrass, and numerous broadleaf weeds. This herbicide should always be applied with a surfactant. There are no grazing or haying restrictions for this herbicide. Other herbicides with the same active ingredient, such as Cadre, cannot be legally applied to perennial peanuts.

Select Max

or TapOut

clethodim

Select Max will provide excellent control of annual and perennial grasses, but will not control any broadleaf weeds. Select Max can be applied up to 32 fl. oz/A in a single treatment, but should not exceed a total of 64 fl. oz/A/year. This product requires the addition of a surfactant or crop oil, and haying or grazing must be delayed for 40 days after application.

Clethodim 2EC

(Several brands)

Clethodim

Apply 6–16 oz/A, plus crop oil at 1%, for control of annual or perennial grasses. For common bermudagrass control, two applications of 16 oz/A, made 2–4 weeks apart, will be required. Do not exceed greater than 32 oz/A/season and do not harvest within 40 days of application.

Velpar L

Hexazinone

On established stands, apply 1 pt/A for control of winter weeds when perennial peanut is dormant. If weeds are emerged at time of application, use surfactant at 1 pt/100 gal. If perennial peanut is not dormant during the time of the application, expect injury and yield loss. During the season, Velpar can be applied after hay removal, but before perennial peanut regrowth has occurred. In this situation, no surfactant is needed, but weed control is often marginal. If peanuts have leafed out, expect moderate to severe injury.

Note: Velpar is toxic to certain hardwood species, particularly oaks. Application near the root zone of sensitive trees can result in tree death. Therefore, be cautious when applying near field borders where desirable trees are growing.

Footnotes

1.

This document is SS-AGR-261, one of a series of the Agronomy Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date December 2005. Revised March 2013. Visit the EDIS website at http://edis.ifas.ufl.edu.

2.

Jason Ferrell, associate professor, Agronomy Department; Brent Sellers, associate professor, Agronomy Department, Range Cattle Research and Education Center, Ona, FL; Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville FL 32611.

The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products named, and references to them in this publication do not signify our approval to the exclusion of other products of suitable composition. Use herbicides safely. Read and follow directions on the manufacturer's label.


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.