Creeping Bentgrass

Note Also see GRASS SEED-New and Established for herbicides that may be used on many species of grass grown for seed.

dimethenamid-P (Outlook)

Rate 0.66 to 0.98 lb ai/A (14 to 21 fl oz/A Outlook)

Time Apply in fall before targeted weeds emerge, or in midwinter in a sequential-use program with other herbicides that control emerged weeds.

Remarks Grass seed crops must be established at least 1 year, or have had at least one seed crop harvested before Outlook is applied. Apply higher rates where denser weed infestations are expected. Excessive straw on the field after harvest may reduce weed control. Sufficient rain or irrigation after application is needed for optimum weed control. May be applied by ground or by air (see label).

Caution Do not apply Outlook in tank-mixtures with other herbicides unless risk of crop injury is acceptable. Subsequent applications may injure crop. Do not allow livestock to graze treated fields for 60 days after application. Treated straw, seed, or seed screenings may be fed to livestock following harvest.

Site of action Group 15: inhibits very long chain fatty acid synthesis

Chemical family Chloroacetamide

ethofumesate (several trade names)

Rate 0.75 to 1.5 lb ai/A

Time Apply to moist soil surface after fall rains start. Apply from preemergence to four-leaf stage of weeds, or before two-leaf stage to control rattail fescue, volunteer wheat and wild oat.

Remarks Controls most annual broadleaf and grass weeds but not annual or perennial ryegrass.

Caution Spray only fields seeded at least 12 months. Mechanically remove or spread all crop residue before spraying. Do not tank mix with other herbicides. Do not graze treated fields. Do not rotate with any crops other than sugar beets or ryegrass for 12 months after application.

Site of action Group 16: unknown

Chemical family Benzofuran

metribuzin (several trade names)

Oregon west of Cascades, and in Crook, Deschutes and Wasco counties

Rate 0.285 to 0.375 lb ai/A

Time When volunteer grasses are in the one- to two-leaf stage of growth after fall rains or irrigation and before active spring growth.

Remarks Apply only to established bentgrass that has had at least one seed harvest. Wait to harvest at least 120 days after applying.

Caution Do not apply to a crop that is under stress. Do not tank mix with other herbicides. Do not apply more than once per year. Allow at least 28 days after application before grazing or using any plant part for livestock feed or bedding. See additional cautions on individual labels.

Site of action Group 5: photosystem II inhibitor

Chemical family Triazinone

oxyfluorfen (Goal 2XL or Galigan 2E)

Oregon and Washington only

Rate 0.125 to 0.375 lb ai/A (8 to 24 fl oz/A Goal 2XL or Galigan 2E)

Time Apply on established stands in fall and midwinter, before and soon after weeds emerge. Apply first before weed (grass) seedlings to be controlled exceed the two-leaf stage, preferably before December 15. Make final applications before mid-January.

Remarks Apply to established fields with at least six tillers per plant. Fields may be treated more than once but with no more than a total of 24 oz/A during a crop season. Goal and Galigan SLN labels vary by state.

Caution Applications may substantially discolor crop foliage; leaf chlorosis and reduced vegetative growth are typical plant responses. If tank mixed with diuron, do not exceed 1.2 lb ai/A diuron in a season. Review the specific oxyfluorfen SLN you are using for updated preharvest and grazing restrictions.

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

Chemical family Diphenylether

pendimethalin (Prowl H2O)

Rate 2 to 3 lb ai/A (4.2 to 6.3 pints/A Prowl H2O)

Time Apply at the beginning of significant fall rains and before weeds germinate. Treatments are most effective with adequate rain or overhead irrigation within 7 days after application.

Remarks For established grass fields only (six or more tillers). Prowl will not control established weeds. See label for specifics on tank-mixes with other herbicides. Removing excessive straw and crop residues may increase effectiveness. Fall applications made to perennial grasses which exceed 6 inches in height may result in reduced weed control due to reduced spray coverage to bare soil.

Caution May temporarily injure grass stands. Tank-mixtures and applications in extreme weather and to weak stands may increase crop injury. Do not harvest forage from treated fields within 45 days of application or harvest hay from treated fields within 60 days of application. The PHI for seed production is 90 days and grass seed screenings may not be used in livestock feed. Grass seed straw from treated fields may be fed to livestock and treated fields may be grazed after harvest. Refer to main labels for crop rotation restrictions.

Site of action Group 3: microtubule assembly inhibitor

Chemical family Dinitroaniline

S-metolachlor (several trade names)

Rate 0.95 to 1.27 lb ai/A

Time Apply to established stands just before, during, or immediately after the first fall rains or an irrigation. Treat target weeds before they emerge.

Remarks Apply only to stands harvested for seed at least once or planted at least 1 year before treatment. Rain or irrigation is required after application and before weeds emerge for best weed control.

Caution Apply only once per crop season. Do not apply after November 15. Tank-mixtures with postemergence herbicides may injure crop. See specific labels for grazing and feeding restrictions based on geography.

Site of action Group 15: inhibits very long chain fatty acid synthesis

Chemical family Chloroacetamide