Weed Management in Pastures - Crop and Soil Science - Lecture Slides, Slides of Botany and Agronomy

Download Weed Management in Pastures - Crop and Soil Science - Lecture Slides and more Slides Botany and Agronomy in PDF only on Docsity! a = ee BAY Yere Pr rrCeaiezae in aU . a aia ty ee ‘1 O0Sity.com Pasture Weed Issues • Lack of management - fertility, lime, mowing, overgrazing • Only 15% of Georgia pastures are sprayed on annual basis • Grazing restrictions • Legume tolerance Docsity.com Fertility Examples for the Southeast • Broomsedge – General indicator of low pH (<5.4), low P and low K – Affected by grazing • Sericea lespedeza – Extremely tolerant of low pH, P and K • Bahiagrass and Common Bermudagrass – More tolerant of low K than hybrid bermudagrass – Also more tolerant of close grazing Docsity.com Effect of Grazing on Weed Control • Grazing is SELECTIVE defoliation • Unlike mowing this may allow greater pressure to be placed on a single forage species – Shift competitive advantage toward favorable species • Can alter selectivity with animal species, stocking rate and timing Docsity.com Vegetation Preferences 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Cattle Goats Horse WT Deer % o f di et Browse Leg/BL Weeds Grass S. Forages 3rd Ed. Docsity.com Do we really want to eliminate all weeds from pastures? Docsity.com Docsity.com Positive Attributes of “Weeds” in Pastures • Can dilute toxins in tall fescue during critical times – Chickweed, crabgrass, dallisgrass, lespedeza • Can extend grazing season and improve productivity – Crabgrass in tall fescue • Can improve quality – Crabgrass Chickweed, curly dock, shepherds purse and tall fescue mixture. Eatonton GA Docsity.com When do you spray? • Winter annuals - henbit, chickweed, buttercups, thistles – November through March • Summer annuals - spiny amaranth, bitter sneezeweed – April through mid-July • Perennials – growth stage dependent Docsity.com Herbicide Options • 2,4-D • dicamba (Vanquish, Banvel) • 2,4-D + dicamba (WeedMaster, others) • dicamba+ diflufenzopyr (Overdrive) • triclopyr (Remedy) • 2,4-D + triclopyr (CrossBow) • triclopyr + clopyralid (Redeem) • 2,4-D + picloram (Grazon P+D, GunSlinger) • fluroxypyr + picloram (Surmount) • fluroxypyr + triclopyr (PastureGard) Docsity.com Herbicide Options (cont.) • aminopyralid (Milestone) • aminopyralid + 2,4-D (ForeFront) • diuron (Direx, Diuron) • metsulfuron (Cimarron) • metsulfuron + chlorsulfuron (Cimarron Plus) • metsulfuron + 2,4-D + dicamba (Cimarron MAX) • hexazinone (Velpar) • sulfosulfuron (Maverick) – Section 18 2006 • tebuthiuron (Spike) • paraquat (Gramoxone Extra) • glyphosate (Roundup UltraMax) • imazapic (Plateau) (no longer an option) Docsity.com Remedy • Grazing and haying restrictions • Beef grazing - 0 d Dairy grazing - 14 d – Hay - 7 d (all livestock types, except lactating dairy cattle, next growing season) – Slaughter - 3 d Docsity.com Basal Stem Spray 1. Stems should be less than 4 inches in diameter. 2. More effective on trees with smooth bark. 3. Can be done anytime. Easiest to do during the dormant season. Mix: 80% diesel fuel or vegetable oil + 20% Remedy by volume. Docsity.com Basal Sprays Docsity.com Cimarron • 60DF metsulfuron • DuPont is phasing out Ally brand name for pastures • Effective for ‘Pensacola’ bahiagrass, spiny amaranth, curly dock, buttercup, wild garlic control, blackberry • Poor horsenettle control • Injurious to legumes & ryegrass (4 mo plant back) Docsity.com Cimarron • 0.1 to 0.3 oz. product per acre • Use low rates on tall fescue and timothy • Do not mix with liquid fert. for bahiagrass control • 0 d grazing or haying restriction - all livestock Docsity.com Cimarron Plus • Two-way product • 48% metsulfuron + 15% chlorsulfuron (63DF) • Effective for ‘Pensacola’ bahiagrass, spiny amaranth, curly dock, buttercup, wild garlic control, blackberry, dewberry, honeysuckle • Poor horsenettle control • Injurious to legumes & ryegrass (4 mo plant back) Docsity.com Cimarron MAX • Grazing Restrictions – Lactating dairy animals – 7 days – Other livestock species – 0 days • Haying Restrictions – All livestock – 37 days Docsity.com Grazon P+D, GunSlinger • 2.0 lbs./gal. 2,4-D amine + 0.54 lbs./gal. picloram amine • Excellent control of broadleaf weeds • Excellent on horsenettle and tropical soda apple • For horsenettle, use 3 pts./acre at early bloom. • About 30 d residual control • Fair control of blackberry Docsity.com Grazon P+D, GunSlinger • Injurious to clovers • Apply to seedling grasses or overseeded small grains at tiller growth stage, 1.5 pts./acre or less • Newly-sprigged bermuda – 1.5 pts./acre, delay until stolons are 6 inches long • Beef grazing - 0 d Dairy grazing - 7 d – Hay - 30 d (all livestock types) – Slaughter - 3 d Docsity.com Plateau • BASF will no longer market to private landowners • grass roadsides, wildflowers, noncropland sites • WHY??? – Economics – Low sales,objections to injury – Can make more money in other markets Docsity.com Newly-sprigged Bermuda • Direx 4L, Diuron 4L • Karmex is not labeled for this use • Plant sprigs 2 inches deep • Apply immediately after sprigging • Use 3.0 to 4.0 pts./acre • Not labeled in established bermudagrass • Annual grasses and broadleaf weeds • 70 day grazing restriction Docsity.com Newest Herbicides • PastureGard - fluroxypyr + triclopyr (Remedy) – controls annual, perennial, & woody species; enhanced control of blackberry • Surmount – fluroxypyr + picloram – controls annual, perennial, & woody species • Milestone – aminopyralid • ForeFront – aminopyralid + 2,4-D • Maverick - sulfosulfuron Docsity.com PastureGard • Beef and other livestock grazing - 0 d • Dairy grazing – not permitted during the growing season of application • Hay – 14 d (all livestock types) Docsity.com Reseeding Restrictions – PastureGard • Cool-season grasses and small grains - 21 days • Clover and other legumes – 30 days • Other crops – 120 days • Labeled for use on permanent grass forage systems – This includes permanent pastures that are overseeded with winter forages. Docsity.com Surmount • 1.19 lbs./gal. picloram amine + 0.96 lbs. gal. fluroxypyr amine • Controls broadleaf weeds, horsenettle, tropical soda apple, and pricklypear cactus. • Apply 3 to 4.0 pts./acre for prickly pear cactus in fall months, control is very slow, about 2 yrs. • About 30 d residual control • Excellent control of upright-growing blackberry (3 to 4 pts./acre) Docsity.com Surmount- It’s Good - BUT!!!!! • Do not – use hay from treated areas for compost or mulch – transfer livestock to untreated areas without 7 d cleanout – use manure for fertilizing broadleaf crops – use in any temporary forage system involving broadleaf crops • USE ONLY ON PERMANENT GRASS FORAGE SYSTEMS Docsity.com Milestone • 2.0 lbs./gal. aminopyralid • Use rate: 4.0 to 7.0 fl. ozs./acre • Numerous broadleaf weeds – thistles, horsenettle, buttercup • Do not seed legumes year of application (additional research being conducted) • Delay application until grasses have 4 to 5 leaves. Docsity.com Milestone • Non-volatile • Injurious to legumes • No grazing or hay restriction for any type of livestock • Weak on sida species, dogfennel, plantains, blackberry, wild radish, other mustards. • Add 2,4-D or Remedy for weeds above. Docsity.com Comparison of Grazon P+D, Surmount, PastureGard, Milestone and Forefront Herbicide Active Ingredient Grazon P+D, GunSlinger 2,4-D picloram Surmount fluroxypyr picloram PastureGard fluroxypyr triclopyr Milestone aminopyralid Forefront aminopyralid 2,4-D Docsity.com Comparison of Grazon P+D, Surmount and PastureGard, Milestone and ForeFront Weed Grazon P+D Surmount PastureGard Milestone Fore- Front Buttercup E G F G-E E Blackberry P-F E E P P Dogfennel G-E E E F F-G Horsenettle G G-E F E E Horseweed E E G E E Pricklypear F-G E F P P Docsity.com Maverick - Monsanto • Sulfosulfuron, 75WDG • Section 18 in GA, AL, MS, AR, OK, LA APPROVED FOR 2007 • Controls johnsongrass and sedges in bermudagrass and bahiagrass • Use rate – 1.33 ozs./acre • Add a nonionic surfactant at 0.25% v/v. Docsity.com Winter Forages • Annual ryegrass • Wheat • Oats • Rye Docsity.com When do you spray? • Winter annuals - henbit, chickweed, buttercups, thistles, wild radish (turnips) – November through March • Grass and Small Grain Forages – Delay application until the 4 to 5 leaf growth stage Docsity.com Tolerance of 2- to 4-Leaf Wheat to Herbicides • 2,4-D (1 and 2 pt. rates) • Weedmaster (1, 2 and 4 pt. rates) • Grazon P+D (1, 2 and 4 pt. rates) • Sprayed in mid-December • 2- to 4-leaf wheat Docsity.com 2,4-D • Amines and esters • Delay application until grasses have 4 to 5 leaves – For grain production delay appl. until fully tillered • Use up to 2.0 pts./acre, except on oats use 1.0 pt./acre • Weak on chickweed and henbit • Good on buttercup, wild radish and other mustards Docsity.com 2,4-D • Grazing and haying restrictions varies by product • Weedar 64 – Beef cattle – 0 days – Lactating dairy animals – 7 days – Hay – all types – 30 days Docsity.com WeedMaster • 2.87 lbs. 2,4-D + 1.0 lb. dicamba per gallon • Delay application until grasses have 4 to 5 leaves • Use up to 2.0 pts./acre, except on oats use 1.0 pt./acre • Better than 2,4-D on chickweed and henbit • Grazing restrictions: only lactating dairy cows – 7 days • Hay/silage: 37 days, all livestock types Docsity.com