General

2,4-D (several products)

Rate 0.7 to 2 lb ae/A, depending on weed species and size

Time Depends on target weeds. Apply to CRP when annual and biennial broadleaf weeds are small and actively growing, and established perennials are at bud stage, unless indicated otherwise on the label.

Remarks Controls many broadleaf weeds. The smaller the annual weeds, the easier they are to control. Spray biennial species in the seedling to rosette stage, before flower stalks are apparent. Spray perennial weeds while still seedlings (coming from seed), or wait until bud stage of growth.

Caution Do not allow drift to desirable vegetation. Do not apply to newly seeded areas until grass is well established. Many forbs (desirable broadleaf plants) can be seriously injured or killed.

Site of action Group 4: synthetic auxin

Chemical family Phenoxy acetic acid

2,4-DB (several products)

Rate 1 to 3 quarts/A

Time Apply postemergence to grasses with at least six leaves and to forage legumes (seedling or established alfalfa, seedling birdsfoot trefoil, seedling alsike clover, seedling ladino clover, or seedling red clover) that are emerged and actively growing.

Remarks Weeds must be small to achieve adequate control.

Caution Do not use on sweet clover, peas, or other legumes not mentioned above. Do not spray when temperatures exceed 90°F.

Site of action Group 4: synthetic auxin

Chemical family Phenoxy acetic acid

aminopyralid (Milestone)

Rate 0.0625 to 0.109 lb ae/gal (4 to 7 fl oz/A Milestone), depending on specific weed species

Time Annual and biennial thistles and knapweeds: optimum time is from rosette to bolting stage, or in the fall on seedlings. Perennial thistles and knapweeds, leafy spurge: optimum time is when fully emerged in spring up to bud growth, and in the fall before a killing frost.

Remarks Uniform coverage is needed for best results. Residual activity will help control later-emerging weeds. Consult label for grazing and haying restrictions.

Caution Do not use if loss of legume species or other broadleaf species cannot be tolerated.

Site of action Group 4: synthetic auxin

Chemical family Pyridine

aminopyralid + 2,4-D (ForeFront)

Rate 0.077 to 0.103 lb ae/A aminopyralid + 0.624 to 0.833 lb ae/A 2,4-D (1.5 to 2 pints/A ForeFront), depending on specific weed species, or up to 5 pints/A as a spot treatment.

Time Use lower rates on small, actively growing broadleaf weeds; increase rate as season progresses and plants mature.

Remarks Consult label for grazing and haying restrictions.

Caution Do not use if loss of legumes species or other broadleaf species cannot be tolerated.

Site of action (both) Group 4: synthetic auxin

Chemical family (aminopyralid) pyridine; (2,4-D) phenoxy acetic acid

aminopyralid + metsulfuron (Chaparral, Opensight)

Rate 0.049 to 0.108 lb ae/A aminopyralid + 0.0089 to 0.019 lb ai/A metsulfuron (1.5 to 3.3 oz/A Chaparral)

Time Apply to actively growing broadleaf weeds. Consult label for application rates for specific weeds.

Remarks A nonionic surfactant applied at 0.25% v/v or crop oil concentrate applied at 1% v/v of spray enhances control under adverse environmental conditions. Chaparral controls many broadleaf weeds. Application rate depends on weed species and stage of growth. Consult label for grazing and haying restrictions.

Caution Do not let spray drift onto desirable vegetation. Many forbs (desirable broadleaf plants in CRP) will be seriously injured or killed.

Site of action Group 4: synthetic auxin; Group 2: acetolactate synthase (ALS) inhibitor

Chemical family (aminopyralid) Pyridine; (metsulfuron) Sulfonylurea

aminopyralid + triclopyr (Capstone)

Rate 0.05 to 0.075 lb ae/A aminopyralid + 0.5 to 0.75 lb ae/A triclopyr (4.0 to 6.0 pints/A Capstone)

Time Apply to actively growing broadleaf weeds and woody plants. Consult label for application rates for specific weed and tree species.

Remarks A nonionic surfactant applied at 0.25% to 0.5% v/v of spray solution enhances control under adverse environmental conditions. Application rate depends on weed species and stage of growth. Consult label for grazing and haying restrictions.

Caution Do not let spray drift onto desirable vegetation. Many forbs (desirable broadleaf plants in CRP) will be seriously injured or killed.

Site of action (both) Group 4: synthetic auxin

Chemical family (both) Pyridine

aminopyralid + florpyrauxifen-benzyl (DuraCor)

Rate 1 oz ae/A aminopyralid + 0.01 oz ae/A florpyrauxifen-benzyl to 1.66 oz ae/A aminopyralid + 0.17 oz ae/A florpyrauxifen-benzyl (12 to 20 oz/A DuraCor). Recommended rate varies by target species and growth stage, see label for details.

Time Apply to small actively growing weeds for best results. Use higher rates for larger weeds or stressful conditions, and for improved soil residual persistence. Apply only to well-established perennial grasses, some species may be tolerant to earlier applications, see label for full details.

Remarks Florpyrauxifen-benzyl improves control of several species not well controlled by aminopyralid alone (Milestone), and increases soil residual. Can be used to treat terrestrial weeds up to the water's edge and in some seasonally dry wetland sites, see label for full restrictions.

Caution Do not apply more than 20 oz/A DuraCor per year. Do not make more than 2 applications per year, or re-treat within 30 days. Do not transfer animals fed on treated grasses to areas in which sensitive broadleaf crops may occur without a 3-day waiting period on untreated pasture. Both active ingredients can accumulate and persist in manure and damage sensitive plants for years after application. Note restrictions on hay for export.

Site of action (both) Group 4: synthetic auxin

Chemical family (both) Pyridine

aminopyralid + florpyrauxifen-benzyl (TerraVue)

Rate 0.18 oz ae/A aminopyralid + 0.02 oz ae/A florpyrauxifen-benzyl to 0.26 oz ae/A aminopyralid + 0.24 oz ae/A florpyrauxifen-benzyl (2 to 2.85 oz/A TerraVue). Recommended rate varies by target species and growth stage, see label for details.

Caution Do not apply more than 2.85 oz/A TerraVue per year unless attempting total vegetation control and then do not apply more than 5.7 oz/A TerraVue per year. Do not transfer animals fed on treated grasses to areas in which sensitive broadleaf crops may occur without a 3-day waiting period on untreated pasture. Both active ingredients can accumulate and persist in manure and damage sensitive plants for years after application, Note restrictions on hay for export and crop rotations.

Site of action (both) Group 4: synthetic auxin

Chemical family (both) Pyridine

atrazine (several products)

Rate 1 to 2 lb ai/A (1 to 2 quarts/A product)

Time For use in establishment or renovation of CRP grasslands. Preemergence applications of atrazine generally result in the greatest levels of weed suppression.

Remarks See atrazine labels for listing of specific grass species that are tolerant to atrazine applications. Atrazine will control a wide variety of grass and broadleaf weed species common in CRP.

Caution Atrazine labels for use in CRP vary by state and by specific products. In Oregon, do not apply more than 2.0 lb ai/A of atrazine for any application, and make no more than one application per year. Restrictions on grazing and haying under emergency conditions vary by label.

Site of action Group 5: photosystem II inhibitor

Chemical family triazine

bromoxynil (Broclean, Maestro, and others products)

Rate 0.25 to 0.50 lb ae/A (1 to 2 pints/A Broclean)

Time Apply spring or fall after grasses have reached the two- to three-leaf stage to control broadleaf weeds. If alfalfa is planted, apply after the four-trifoliolate leaf stage.

Remarks Can be applied safely to alfalfa. Most effective on small weeds, defined as the four-leaf stage, 2 inches high, or 1 inch in diameter, whichever comes first.

Caution Do not apply to alfalfa when air temperature is expected to exceed 80°F.

Site of action Group 6: photosystem II inhibitor

Chemical family Nitrile

bromoxynil + MCPA (Bronate or WildCard XTRA)

Rate 0.25 to 0.50 lb ai/A each (1 to 2 pints/A Bronate or WildCard XTRA)

Time Apply in spring or fall after grasses have reached the three-leaf stage to control broadleaf weeds.

Caution Do not apply to grasses seeded with alfalfa; legumes may be severely injured.

Site of action (bromoxynil) Group 6: photosystem II inhibitor; (MCPA) Group 4: synthetic auxin

Chemical family (bromoxynil) nitrile; (MCPA) phenoxy acetic acid

bromoxynil + MCPA + fluroxypyr (Carnivore)

Rate 0.20 to 0.41 lb ai/A bromoxynil + 0. 20 to 0.41 lb ae/A MCPA + 0.08 to 0.167 lb ae/A fluroxypyr (1 to 2 pints/A Carnivore)

Time Apply to weeds up to the 4-leaf stage, or 8 inches high. Certain larger weeds may be controlled; see label for size recommendations and application timings.

Remarks Do not apply when weeds are under moisture stress. Do not apply more than 2.4 pints/A of Carnivore per growing season. Selective control of broadleaf weeds and volunteer potatoes.

Site of action (bromoxynil) Group 6: photosystem II inhibitor; (MCPA and fluroxypyr) Group 4: synthetic auxin

Chemical family (bromoxynil) nitrile; (MCPA) phenoxy acetic acid; (fluroxypyr) pyridine

bromoxynil + pyrasulfotole (Huskie)

Rate 0.228 to 0.254 lb ai/A (13.5 to 15 oz/A Huskie)

Time See label for weed size recommendations and application timings, but control of most species is best at the 15 fl oz/A rate when weeds have from one to six leaves. Two applications of Huskie can be made per year, separated by at least 30 days.

Remarks For most consistent weed control under adverse growing conditions, add AMS or an ammonium nitrogen source as directed by the spray additives section of the label. Huskie may be tank mixed with a variety of other broadleaf herbicides labeled for use in CRP; see label for instructions.

Caution Do not exceed 30 oz/A of Huskie per year. Aerial and chemigation applications are prohibited.

Site of action (bromoxynil) Group 6: photosystem II inhibitor;(pyrasulfotole) Group 28: inhibits 4hydroxyphenylpyruvatedioxygenase (4-HPPD)

Chemical family (bromoxynil) nitrile; (pyrasulfotole) isoxazole

carfentrazone (Aim EC)

Rate 0.008 to 0.031 lb ai/A (0.5 to 2 fl oz/A Aim EC)

Time Treat when weeds are small.

Remarks Apply with ground equipment using at least 10 gal/A of finished spray. See label for control of specific weeds and adjuvant recommendations.

Caution Allow at least 7 days between applications; do not exceed 5.9 fl oz/A or three treatments per season.

Site of action Group 14: protoporphyrinogen oxidase inhibitor

Chemical family Triazinone

chlorsulfuron (Telar)

Rate 0.012 to 0.062 lb ai/A

Time Preemergence or postemergence in early stages of weed growth.

Remarks Label lists specific rates by weed species. Treat Canada thistle prebloom to bloom and/or at fall rosette.

Caution Chlorsulfuron severely injures broadleaves such as clover and alfalfa.

Site of action Group 2: acetolactate synthase (ALS) inhibitor

Chemical family Sulfonylurea

clopyralid (Transline, Stinger)

Rate 0.124 to 0.49 lb ae/A (0.33 to 1.33 pints/A product). Higher rates are for deep-rooted perennial weeds and less-than-ideal conditions.

Time Apply when weeds are young and actively growing.

Remarks Conifers and non-leguminous broadleaf trees are generally tolerant. Alfalfa is moderately tolerant. Sweet clover is tolerant.

Caution Ground application only.

Site of action Group 4: synthetic auxin

Chemical family Pyridine

clopyralid + 2,4-D (Curtail)

Rate 0.19 to 0.38 lb ae/A clopyralid + 1 to 2 lb ae/A 2,4-D (2 to 4 quarts/A Curtail). High rates are for deep-rooted perennial weeds.

Time Apply to established grasses when weeds are actively growing.

Caution Do not use if broadleaf plants are a desired cover. Read label for plant-back restrictions if rotating ground out of CRP. Do not apply by air during an air temperature inversion.

Site of action Group 4: synthetic auxin

Chemical family Pyridine

clopyralid + fluroxypyr (WideMatch or Colt AS)

Rate 0.125 to 0.25 lb ae/A each (1.33 to 2.66 pints/A product), not to exceed 0.49 lb ae/A (5.33 pints/A) per season

Time Apply broadcast postemergence, when weeds are actively growing, but before 8 inches tall. To control perennial weed such as Canada thistle, apply when basal leaves are fully emerged up to bud stage.

Caution Do not use if broadleaf plants are a desired cover. Read label for plant-back restrictions if rotating ground out of CRP. Do not apply by air during an air temperature inversion.

Site of action (both) Group 4: synthetic auxin

Chemical family (both) pyridine

dicamba (Banvel or Clarity) + 2,4-D

Rate 0.12 to 2 lb ae/A dicamba + 0.25 to 1 lb ae/A 2,4-D

Time After grasses have three leaves in the establishment year, or in fall or spring on grasses more than 1 year old.

Remarks Use up to 0.25 lb ae/A dicamba and up to 0.5 lb ae/A 2,4-D in the establishment year. Do not spray stressed grasses.

Caution Legumes are sensitive to dicamba and 2,4-D

Site of action (both) Group 4: synthetic auxin

Chemical family (dicamba) benzoic acid; (2,4-D) phenoxy acetic acid

dicamba + 2,4-D (Weedmaster, Latigo or Rifle)

Rate Refer to label for rate selection based on targeted weed or brush species. Application rates of 4 pints/A for spot treatments only.

Remarks Do not spray when grasses are stressed.

Caution Legumes are sensitive to dicamba and 2,4-D.

Site of action (both) Group 4: synthetic auxin

Chemical family (dicamba) benzoic acid; (2,4-D) phenoxy acetic acid

dicamba + diflufenzopyr (Distinct or Overdrive)

Rate 0.125 to 0.25 lb ae/A dicamba + 0.05 to 0.10 lb ae/A diflufenzopyr (4 to 8 oz/A Distinct or Overdrive)

Time Apply to CRP when annual and biennial broadleaf weeds are small and actively growing. Can also be applied in the fall to senesced knapweed species for control the following spring.

Remarks Controls broadleaf weeds. The smaller the annual weeds, the easier they are to control. Spray biennial species in the seedling to rosette stage, before flower stalks are apparent.

Caution Do not allow drift to desirable vegetation. Do not apply to newly seeded areas until grass is well established. Many forbs (desirable broadleaf plants) and legumes can be seriously injured or killed by applications. Use with a nonionic surfactant or methylated seed oil to maximize weed control efficacy.

Site of action (dicamba) Group 4: synthetic auxin: (diflufenzopyr) Group 19: auxin transport

Chemical family (dicamba) benzoic acid; (diflufenzopyr) semicarbazone

dicamba + halosulfuron (Yukon)

Rate 0.03 to 0.06 lb ai/A halosulfuron + 0.14 to 0.28 lb ae/A dicamba (4 to 8 oz/A Yukon)

Time Apply to CRP when annual and biennial broadleaf weeds and yellow nutsedge are small and actively growing.

Remarks Controls broadleaf weeds and yellow nutsedge. The smaller the annual weeds, the easier they are to control. Spray biennial species in the seedling to rosette stage, before flower stalks are apparent.

Site of action (dicamba) Group 4: synthetic auxin: (halosulfuron) Group 2; acetolactate synthase (ALS) inhibitor

Chemical family (dicamba) benzoic acid; (halosulfuron) sulfonylurea

fluroxypyr (Starane Ultra and several products)

Rate 0.14 to 0.245 lb ai/A fluroxypyr

Time For best performance, apply to emerged and actively growing broadleaf weeds less than 4 to 8 inches in height. Only weeds that have emerged at time of application will be controlled.

Remarks Do not use on land with desirable legumes, clovers, or other sensitive broadleaf plants.

Caution Grazing or haying CRP treated with fluroxypyr is prohibited.

Site of action Group 4: synthetic auxin

Chemical family Pyridine

fluroxypyr + 2,4-D (Starane + Salvo)

Rate 0.125 to 0.25 lb ae/A fluroxypyr + 0.49 to 1.0 lb ae/A 2,4-D (1.33 to 2.66 pints/A Starane + Salvo)

Time Weeds must be small, actively growing, and less than 8 inches tall.

Caution Do not use on land with desirable legumes, clovers, or other sensitive broadleaf plants.

Site of action (both) Group 4: synthetic auxin

Chemical family (fluroxypyr) pyridine: (2,4-D) phenoxy acetic acid

glyphosate (several products)

Rate 0.28 to 0.38 lb ae/A to control small (2 to 4 inch) grasses and certain broadleaf weeds. For perennial weeds, use 0.75 to 3.75 lb ae/A. Consult labels for rates for specific weeds.

Time Apply to actively growing weeds any time before planting, or before desirable grasses or legumes emerge. For selective broadcast applications, apply in early spring before desirable grasses break dormancy. Late fall applications can be made after desirable grasses have gone dormant.

Remarks Add 2 quarts of a nonionic surfactant, 80% ai or more, to each 100 gal of spray solution. Ammonium sulfate added to spray solution at 17 lb/100 gal may increase effectiveness on environmentally stressed plants. See label for additive rates for nonionic surfactants and ammonium sulfate.

Caution Glyphosate will kill any crop seedlings it contacts.

Site of action Group 9: inhibits EPSP synthase

Chemical family Glycine

halosulfuron (Sandea)

Rate 0.03 to 0.06 lb ai/A halosulfuron (0.66 to 1.33 oz/A Sandea)

Time Apply to CRP when yellow nutsedge is small and actively growing.

Remarks Controls yellow nutsedge. May be applied as a postemergence broadcast application or as a spot treatment. A second spot treatment may be necessary to control yellow nutsedge. Use with a nonionic surfactant or methylated seed oil to maximize weed control efficacy.

Caution Do not allow drift to desirable vegetation. Do not apply more than 1.33 oz of Sandea per year. There are no grazing restrictions following Sandea applications. Forage preharvest interval is 37 days.

Site of action Group 2; acetolactate synthase (ALS) inhibitor

Chemical family Sulfonylurea

indaziflam (Rejuvra)

Rate Grazed areas 0.046 to 0.065 lb ai/A (3.5 to 5 oz/A Rejuvra); areas not grazed or cut for hay 0.046 to 0.09 lb ai/A (3.5 to 7 oz/A Rejuvra). Use lower rates only where weed pressure is light and shorter period of residual activity is desired.

Time Apply at least several weeks prior to expected germination of targeted weeds. Apply to dry soils when rain is not expected for at least 48 hr. Can be successfully applied several months in advance of weed germination.

Remarks For release of desirable perennial species for rangeland and CRP restoration, Indaziflam provides multiple years of pre-emergent control of germinating seeds of most species from a single application. Provides excellent control of winter annual grass weeds (e.g. cheatgrass, medusahead, feral rye, etc.). Indaziflam is safe over the top of most well-established perennial grasses. Use only in areas in which desirable perennial grass stands are of adequate density to meet management goals for several years after application without any further plant recruitment. Do not expect to conduct successful seedings of desirable plants for several years after application. Pre-emergent activity only, use appropriate tank-mix partners if weeds have emerged prior to application. Does not control established perennial weeds.

Caution Adequate binding time on dry soil reduces risk of indaziflam moving into the root zone of desirable plants. Do not apply to or around water. Do not apply to saturated, frozen, or snow-covered ground. Do not harvest hay within 40 days of application. Do not exceed a maximum rate of 0.065 lb ai/A (5 oz/A Rejuvra) in a single application. On grazed areas, do not apply more than 0.078 lb ai/A (6 oz/A Rejuvra) in a 12-month period. Do not make more than 2 applications in a 12-month period. Allow at least 60 days between applications.

Site of action Group 29, inhibition of cellulose biosynthesis

Chemical family Alkylazine

MCPA (several products)

Rate 0.46 to 1.39 lb ae/A (1 to 3 pints/A MCPA-amine)

Time Apply to annual broadleaf weeds when small and actively growing. Spray perennials in early-bud to full-bloom stage and during re-growth in fall.

Remarks Controls certain annual broadleaf and perennial weeds in CRP.

Caution Do not use this treatment if alfalfa is present and desired. Do not use if temporary injury to clovers cannot be tolerated. Do not use on newly seeded areas until grass is well established.

Site of action Group 4: synthetic auxin

Chemical family Phenoxy acetic acid

metsulfuron (Escort DF and several other products)

Rate 0.1 to 1 oz/A (0.166 to 1.66 oz/A)

Time Apply after weeds emerge, to grasses in the three- to four-leaf stage. Use higher rates on established grasses only.

Remarks Metsulfuron is labeled for use on many native and improved perennial grasses used in the CRP. See label for grass species. It controls a wide range of broadleaf weeds (including Himalayan blackberries) and inhibits Canada thistle growth. It will not control nightshades. For best results, weeds should be actively growing; add a surfactant of at least 80% ai at 1 to 2 quarts/100 gal. Cimarron Max (metsulfuron + dicamba + 2,4-D) and Cimarron Plus and Cimarron X-tra (metsulfuron + chlorsulfuron) are labeled for CRP.

Caution Do not use on soils with a pH greater than 8. Metsulfuron can persist in soil. Carefully follow label instructions on crop rotations when land is taken out of CRP. This material is not recommended for plantings that include a legume.

Site of action Group 2: acetolactate synthase (ALS) inhibitor

Chemical family Sulfonylurea

paraquat (Cyclone, Gramoxone, BonFire, or Firestorm)

Rate 0.25 to 1 lb ai/A (2 to 4 pints/A product)

Time Apply any time before or after planting until desirable plants emerge.

Remarks For best results, use when weeds are small. Always use a nonionic surfactant, crop oil concentrate, or methylated seed oil with the application.

Caution Restricted use pesticide due to acute toxicity. For retail sale to and use only by certified applicators - not to be used by uncertified persons working under the supervision of a certified applicator.

Site of action Group 22: photosystem I electron diversion

Chemical family Bipyridilium

pendimethalin (Pendulum Aquacap, Stealth, Prowl 3.3 and several other products)

Rate 0.41 to 1.03 lb ai/A (1 to 2.5 pints/A Aquacap)

Time Apply preplant incorporated or preemergence before annual grasses and broadleaf weeds germinate.

Remarks Rate depends on soil type and organic matter content. If cover crop is lost because of bad weather, any crop registered for pendimethalin use and application method can be replanted the same year. If replanting, do not rework soil deeper than the pendimethalin-treated zone.

Caution Do not feed or graze CRP legume cover crops established after application. Do not use on peat or muck soils. The legume cover crop may be reduced somewhat.

Site of action Group 3: microtubule assembly inhibitor

Chemical family Dinitroaniline

pendimethalin + dimethenamid (Freehand 1.75G)

Rate 1.0 to 2.0 lb ai/A pendimethalin + 0.75 to 1.5 lb ai/A dimethenamid (100 to 200 lb/A Freehand 1.75G)

Time Apply preemergence, before annual grasses and broadleaf weeds germinate.

Remarks For weed management during hardwood or conifer tree establishment or regeneration in CRP. Freehand may be applied at tree planting, or to established trees.

Caution Do not allow Freehand to come into direct contact with seedling tree roots. Do not apply to newly planted tree seedlings until soil is thoroughly packed or settled around the tree roots.

Site of action Group 3: microtubule assembly inhibitor; Group 15: inhibits very long chain fatty acid synthesis

Chemical family (pendimethalin) Dinitroaniline; (dimethenamid) Chloroacetamide

picloram (Tordon)

Rate 0.06 to 0.5 lb ae/A (0.25 to 2 pints/A Tordon)

Time Apply to established grasses when weeds are growing well.

Remarks To control many annual and perennial broadleaf weeds.

Caution A restricted-use herbicide. Legumes are highly sensitive to Tordon. Carefully follow label instructions on crop rotations when land is taken out of CRP.

Site of action Group 4: synthetic auxin

Chemical family Pyridine

pyraflufen (Venue, Vida)

Rate 0.004 to 0.0053 lb ai/A (3.0 to 4.0 fl oz/A Venue); 0.0008 to 0.003 lb ai/A (0.5 oz/A to 2 fl oz/A Vida)

Time Apply to broadleaf seedling weeds that are less than 4 inches tall or less than 3 inches in diameter if in the rosette stage. Thorough, uniform spray coverage is essential for good control of broadleaf weeds.

Remarks For postemergence broadleaf weed control in CRP. May be tank mixed with synthetic auxin herbicides to broaden the weed control spectrum. Always apply with a methylated seed oil or nonionic surfactant at a rate of 0.5% v/v for optimum activity.

Caution Do not exceed two applications per season. Allow a minimum of 14 days between applications.

Site of action Group 14: protoporphyrinogen oxidase (PPO)inhibitor

Chemical family Phenylpyrazole

quinclorac (Paramount, Facet)

Rate 0.14 to 0.75 lb ai/A

Time For the control and suppression of broadleaf perennial weeds and some broadleaf annual species. For field bindweed control apply in fall, but before a killing frost. Field bindweed should be actively growing and at least 4 inches long. Repeat applications are necessary to maintain adequate control.

Remarks Adequate soil moisture and/or light rain after application is required for root uptake. Adding methylated seed oil or crop oil concentrate is required for consistent control. Nitrogen solutions or ammonium sulfate can be added to enhance control but should not replace the MSO or COC.

Site of action Group 4: synthetic auxin

Chemical family Quinoline carboxylic acid

saflufenacil (Sharpen)

Rate 0.022 to 0.045 lb ai/A (1 to 2 fl oz/A Sharpen)

Time Apply to CRP grasses for burndown and residual broadleaf weed control in the fall or spring.

Remarks A methylated seed oil plus ammonium sulfate or urea ammonium nitrate is required for burndown activity. See label for more information on adjuvants and tank-mixes.

Caution Do not exceed 6 fl oz/A per year. Sharpen may cause transitory injury to cool-season grasses under certain conditions. Sharpen may cause severe injury to desirable broadleaf species and legumes.

Site of action Group 14: protoporphyrinogen oxidase (PPO) inhibitor

Chemical family Pyrimidinedione

sulfometuron-methyl (SFM 75)

Rate 0.35 to 0.375 lb ai/A (0.75 to 8 oz/A SFM 75)

Time For preemergence and postemergence control of many grass and broadleaf weeds in CRP.

Remarks Apply when weeds are actively germinating and emerging. Application rates are dictated by weed species and the amount of annual precipitation, with higher applications needed in wetter regions.

Caution Review label for list of tolerant grasses and grass or crop replant intervals following treatment with SFM 75.

Site of action Group 2: acetolactate synthase (ALS) inhibitor

Chemical family Sulfonylurea

triclopyr (Vastlan)

Rate (0.75 to 2 quarts/A Vastlan) depending on whether woody species are present.

Time Apply when woody plants and weeds are actively growing. Adequate soil moisture before and after treatment is important.

Remarks Triclopyr premixed with clopyralid is available as Redeem R&P.

Caution Legumes are sensitive to Remedy.

Site of action Group 4: synthetic auxin

Chemical family Pyridine

triclopyr + 2,4-D (Crossbow, Crossroad)

Rate 0.5 to 1 lb ae/A 2,4-D + 0.25 to 0.5 lb ae/A triclopyr (1 to 2 quarts/A Crossbow) to control annual broadleaf weeds or seedling perennial broadleaf weeds. Use up to 1.5 gal/A Crossbow for established perennials.

Time Apply only when perennial grasses are established and when weeds are growing well. Conditions that stress the grasses will increase potential for injury to grasses.

Caution Legumes are sensitive to Crossbow.

Site of action (both) Group 4: synthetic auxin

Chemical family (triclopyr) pyridine; (2,4-D) phenoxy acetic acid

triasulfuron + dicamba (Rave)

Rate 0.011 to 0.028 lb ai/A triasulfuron + 0.063 to 0.156 lb ai/A dicamba (2 to 5 oz/A Rave)

Time Apply to small, actively growing weeds.

Remarks Label lists established grasses to which Rave can be applied.

Caution Do not apply Rave until at least 60 days after desirable grasses emerge.

Site of action (triasulfuron) Group 2: acetolactate synthase (ALS) inhibitor; (dicamba) Group 4: synthetic auxin

Chemical family (triasulfuron) sulfonylurea; (dicamba) benzoic acid