Pasture and Hay Field Weed Management Dr Tim

Pasture and Hay Field Weed Management Dr. Tim Murphy, Extension Weed Specialist The University of Georgia

Forage Weed Issues v Lack of management - fertility, lime, mowing, overgrazing v No weed control - only 15% of Georgia pastures are sprayed on annual basis v Grazing and haying restrictions v Weedy grass control in hay fields and legume tolerance

Do I spray or fertilize first? v Spray first v Control existing weeds v Begin soil-test based lime and fertilizer program v Establish legumes after good weed control has been practiced for 1 to 2 years

When do you spray? v Winter l annuals - henbit, chickweed, buttercups, thistles November through March v Summer l annuals - spiny amaranth, bitter sneezeweed April through mid-July v Perennials l growth stage dependent

Herbicide Options 2, 4 -D v dicamba (Vanquish, Banvel) v 2, 4 -D + dicamba (Weed. Master) v dicamba+ diflufenzopyr (Overdrive) v triclopyr (Remedy) v 2, 4 -D + triclopyr (Cross. Bow) v triclopyr + clopyralid (Redeem) v 2, 4 -D + picloram (Grazon P+D) v fluroxypyr + picloram (Surmount) v fluroxypyr + triclopyr (Pasturegard) v

Herbicide Options (cont. ) v diuron (Direx, Diuron) metsulfuron (Cimarron) v metsulfuron + 2, 4 -D + dicamba (Cimarron MAX) v hexazinone (Velpar) v tebuthiuron (Spike) v paraquat (Gramoxone Extra) v glyphosate (Roundup Ultra. Max) v imazapic (Plateau) (no longer an option) v

Remedy 4. 0 lbs. /gal. triclopyr ester v low volatile - but ? ? ? v Excellent on upright blackberry, numerous broadleaf weeds v Good on tropical soda apple v Fair on horsenettle v Poor on pokeweed, honeysuckle, trumpetcreeper v Expensive v

Remedy v Mixes with diesel v Remedy 20% + 80% diesel, excellent as basal application for trees < 4 inch DBH, and spot control of pricklypear cactus and palmetto v Injurious to clovers v Apply to seedling grasses 5 to 6 inches tall or after tiller development

Remedy v Grazing v Beef and haying restrictions grazing - 0 d Dairy grazing - 14 d Hay - 7 d (all livestock types, except lactating dairy cattle, 365 d) l Slaughter - 3 d l

Redeem v 2. 25 lbs. /gal. triclopyr amine + 0. 75 lbs. clopyralid amine v Excellent control aster and legume weeds v Rates: 1. 5 to 4. 0 pts. /acre v Highly injurious to legumes v Alternative to Crossbow, Weed. Master, Grazon P+D

Redeem v Beef and other livestock grazing - 0 d v Dairy grazing - 14 d Hay - 7 d (all livestock types, except lactating dairy cattle, 365 d) l Slaughter - 3 d l

New Products -2005 v Pasture. Gard - fluroxypyr + triclopyr (Remedy) l Broader weed spectrum than triclopyr alone l controls annual, perennial, & woody species; enhanced control of blackberry and dogfennel v Surmount – fluroxypyr + picloram l Broader weed spectrum than fluroxypyr alone l controls annual, perennial, & woody species

Pasture. Gard v 1. 5 lbs. /gal. triclopyr ester + 0. 5 lbs. /gal. fluroxypyr ester v Controls numerous brush species and broadleaf weeds. Upright blackberry, sweet gums, Sericea lespedeza, dogfennel, gallberry, rose species, lantana l Palmetto and yucca – use 2. 0% v/v solution in water l Fair control of horsenettle and tropical soda apple l

Pasture. Gard v Mixes with diesel and other oil carriers v Pasture. Gard 50% + 50% diesel, excellent as basal application for trees < 4 inch DBH v Injurious to clovers v Apply to seedling grasses after tiller development

Pasture. Gard v Beef and other livestock grazing - 0 d v Dairy grazing – not permitted during the growing season of application v Hay – 14 d (all livestock types)

Reseeding Restrictions – Pasture. Gard v Cool-season grasses and small grains - 21 days v Clover and other legumes – 30 days v Other crops – 120 days

Surmount 1. 19 lbs. /gal. picloram amine + 0. 96 lbs. gal. fluroxypyr amine v Controls broadleaf weeds, horsenettle, tropical soda apple, and pricklypear cactus. v Apply 3 to 4. 0 pts. /acre for prickly pear cactus in fall months, control is very slow, about 2 yrs. v About 30 d residual control v Excellent control of upright-growing blackberry (3 to 4 pts. /acre) v

Surmount Injurious to clovers v Apply to seedling grasses or overseeded small grains at tiller growth stage v Newly-sprigged bermuda –delay until stolons are 6 inches long v Beef grazing - 0 d; slaughter 3 d v Lactating Dairy Animals – grazing 14 d; silage 14 d. v Hay – 7 d (all livestock types) v

Reseeding Restrictions – Surmount v Cool-season grasses - 21 days v Clovers – 12 months v Other legumes – 12 months

Surmount- It’s Good - BUT!!!!! v Do not use hay from treated areas for compost or mulch l transfer livestock to untreated areas without 7 d cleanout l use manure for fertilizing broadleaf crops l use in any temporary forage system involving broadleaf crops l v USE ONLY ON PERMANENT GRASS FORAGE SYSTEMS

Grazon P+D v 2. 0 lbs. /gal. 2, 4 -D amine + 0. 54 lbs. /gal. picloram amine v Excellent control of broadleaf weeds v Excellent on horsenettle and tropical soda apple v For horsenettle, use 3 pts. /acre at early bloom. v About 30 d residual control v Fair control of blackberry

Grazon P+D v Injurious to clovers v Apply to seedling grasses or overseeded small grains at tiller growth stage, 1. 5 pts. /acre or less v Newly-sprigged bermuda – 1. 5 pts. /acre, delay until stolons are 6 inches long v Beef grazing - 0 d Dairy grazing - 7 d Hay - 30 d (all livestock types) l Slaughter - 3 d l

Reseeding Restrictions – Grazon P+D v Cool-season grasses - 21 days v Clover - 2 pts. /acre or less l Fall-seeding permitted if Grazon P+D applied no later than June (4 month plant back) v Clover l – 2 to 3 pts. /acre Spring (Feb. – Mar. ) seeding permitted the following spring for applications made no later than Sept. 15 the previous year.

Grazon P+D - It’s Good - BUT!!!!! v Do not use hay from treated areas for compost or mulch l transfer livestock to untreated areas without 7 d cleanout l use manure for fertilizing broadleaf crops l use in any temporary forage system involving broadleaf crops l v USE ONLY ON PERMANENT GRASS FORAGE SYSTEMS

Cimarron v 60 DF metsulfuron v Du. Pont is phasing out Ally v Effective for ‘Pensacola’ bahiagrass, spiny amaranth, curly dock, buttercup, wild garlic control, blackberry v Poor horsenettle control v Injurious to legumes & ryegrass (4 mo plant back)

Cimarron v Now labeled at 0. 1 to 1. 0 oz. product per acre v Use low rates on tall fescue and timothy v Do not mix with liquid fert. for bahiagrass control v 0 d grazing or haying restriction - all livestock

Cimarron MAX v Co-Pack product v Metsulfuron 60 DF + 2, 4 -D amine (2. 87 lbs. /gal. ) + dicamba (1. 0 lb. /gal. ) v Increases number of broadleaf weeds controlled v Use rates 0. 25 to 1. 0 oz. /acre of Cimarron plus 1. 0 to 4. 0 pts. /acre of 2, 4 -D + dicamba v Add nonionic surfactant at 0. 25% v/v

Plateau v BASF will no longer market to private landowners v grass roadsides, wildflowers, noncropland sites v WHY? ? ? Economics l Low sales, objections to injury l Can make more money in other markets l

Newly-sprigged Bermuda v Direx 4 L, Diuron 4 L v Karmex is not labeled for this use v Plant sprigs 2 inches deep v Apply immediately after sprigging v Use 3. 0 to 4. 0 pts. /acre v Not labeled in established bermudagrass v Annual grasses and broadleaf weeds

Overdrive - BASF v Dicamba + diflufenzopyr v Controls broadleaf weeds v 0 day grazing or haying restriction v Limited data base v Primarily will be marketed for rights-of-way use

Summary - Forage Weed Control v Know cropping system v Use approved cultural practices v Identify weeds v Select product v Follow grazing and haying restrictions v Proper application timing