bensulide (Prefar 4-E)
Excluding rutabaga, radish, and horseradish
Rate 5 to 6 lb ai/a (5 to 6 quarts/a)
Time Apply preplant and incorporate 1 to 2 inches deep simultaneously or immediately after application by cross-disking or using a power take-off rotary tiller.
Remarks Consult label for planting sensitive crops after treatment. Does not control nightshade.
Caution Do not exceed one application every 12 months. (Inhibits seedling roots)
Site of action Group 8: lipid synthesis inhibitor but not an ACCase inhibitor
Chemical family Organophosphorus
Cabbage only, pre-transplant only
Rate Depends on soil type and pH. On coarse soils with less than 1% organic matter: apply 0.07 lb ai/a (2.25 fl oz/a), To fine soils with more than 3% OM: apply 0.375 lb ai/a (12 oz/a). Use higher rates when soil pH is less than 7.0, and lower rates when pH is greater than 7.0.
Time Fall or early spring preplant surface or preplant-incorporated.
Remarks Apply in fall or spring up to transplanting, starting 60 days prior. Preplant incorporate to 2 inches.
Caution For use only by individuals or firms certified and/or licensed as pesticide applicators. Do not use on soil with less than 1% OM. Observe rotational guidelines, which may up to 24 months for some crops.
Site of action Group 14: protoporphyrinogen oxidase inhibitor
Chemical family Triazinone
sulfentrazone (Spartan 4F)
Rate 0.07 lb ai/a (2.25 oz/a Spartan 4F) on coarse soil to 0.25 lb ai/a (8 oz/a) on fine soil. Rate also depends on OM content. Use higher rates for soils of pH less than 7.0 and lower rates for pH greater than 7.0.
Time Fall or early spring preplant or preplant-incorporated.
Remarks Apply in fall or spring to suppress weeds up to 60 days before planting horseradish. Preplant-incorporate to 2 inches. Can apply preemergence to soil surface shortly before transplanting or within 5 days after transplanting. Do not exceed 8 oz/a in a 12-month period that begins with the first application. Do not apply directly to emerged crop, or if crop sprouts are near the soil surface.
Caution Observe rotational guidelines, which may be as long as 24 months for some crops.
Site of action Group 14: protoporphyrinogen oxidase (PPO) inhibitor
Chemical family Triazinone
trifluralin (Treflan 4L)
Excluding horseradish and rutabaga
Rate 0.5 to 1 lb ai/a (1 to 2 pints/a Treflan 4L), depending on whether the crop is direct-seeded or transplanted, and on soil texture and organic matter content.
Time Apply as a preplant soil-incorporated treatment before planting or transplanting.
Remarks Direct-seeded crops may be stunted if rates exceed limits for soil type and organic matter content, or if soil texture varies greatly within a field. Chinese cabbage and kohlrabi may be particularly sensitive. Consult label for soil type, OM content, and application instructions.
Site of action Group 3: microtubule assembly inhibitor
Chemical family Dinitroaniline