asulam (ASULOX HERBICIDE EPA# 70506-139, SLN#WA-080001, SLN#OR-070016; Asulam EPA# 34704-904, SLN# WA- 110003, SLN# OR-100008)
Oregon and Washington only
Rate 0.62 to 1.25 lb ai/A (1.5 to 3 pints/A Asulox)
Time Apply postemergence; works best if weeds are small. If applied once per season, use 1.5 pints/A on spinach with two to four leaves, or 3 pints/A on spinach with four to six true leaves. If applied twice per season, use 3 pints/A on spinach with four to eight true leaves and 3 pints/A seven days later (typically 8 to 12 true leaves).
Remarks SLN labels OR-070016 and OR-100008, and WA-080001 and WA-110003. A nonionic surfactant at 0.25% v/v may be added to the spray to increase efficacy. Crop oils and other adjuvants such as urea ammonium nitrate are not recommended. Suggested dilution rate is 20 gal/A water. Spinach may be somewhat stunted, especially with two applications at 3 pints/A.
Caution No pesticide residue tolerance has been established for this crop, and so no portion of this seed crop (including screenings) may be used or distributed for food or feed. Grazing the crop field or stubble is not permitted. Asulam is known to leach through soil into ground water under certain conditions. Using asulam where soils are permeable, particularly where the water table is shallow, may contaminate ground water. Avoid surface water contamination.
Site of action Group 18:dehydropteroate (DHP) synthase inhibitor
Chemical family Carbamate
diquat (Reglone)
see Preharvest Desiccation at end of this section
ethofumesate (NORTRON SC HERBICIDE EPA#264-613, SLN#OR-160003)
Oregon only
Rate 0.75 to 1 lb ai/A (24 to 32 oz/A Nortron SC)
Time Apply preemergence at or shortly after planting but before weeds germinate.
Remarks SLN labels OR-160003. Soon after treatment, 0.5 inch of rain or irrigation is important to activate herbicide. If rain is marginal, incorporate ethofumesate 1 to 2 inches before planting.
Caution Do not apply through any type of irrigation system. Do not rotate with any crops other than sugar beets or ryegrass for 12 months. Do not cultivate deeper than 2 inches; this may reduce effectiveness of ethofumesate.
Site of action Group 15: very long-chain fatty acid synthesis inhibitor
Chemical family Benzofuranes
fluazifop (FUSILADE DX HERBICIDE EPA# 100-1070, WA-040006)
Washington only
Rate 0.063 to 0.25 lb ai/A (4 to 16 oz/A)
Time Apply to actively growing grasses. Results often are erratic on grass stressed from lack of vigor, drought, high temperature, or low fertility.
Remarks SLN label WA-040006. Identify grasses and adjust rates for stage of weed growth and susceptibility as label instructs. More mature grasses and quackgrass can be controlled but may require two applications. Annual bluegrass and all fine fescues resist treatment.
Caution Do not exceed 32 oz/A per season. Do not apply if rain is expected within 1 hr. Do not plant rotation grass crops such as corn and cereals within 60 days of the last application. Grazing any plant product or residue is prohibited.
Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family Aryloxyphenoxypropionate
quizalofop (ASSURE II HERBICIDE EPA# 5481-646)
Rate 0.069 to 0.17 lb ai/A (5 to 12 oz/A Assure II)
Time Apply at optimum growth stage listed on label.
Remarks Identify susceptible grasses, and add 4 quarts crop oil concentrate or 1 quart nonionic surfactant/100 gal spray mix. Grass control may be reduced if applied immediately before or after applying a broadleaf herbicide.
Caution Do not mix with, or apply with, any other pesticide except as label specifies. Do not apply to plants stressed by drought, cold, or injury from herbicides, insects, or disease. Do not use any treated part of crop for food or feed. Do not exceed 25 oz/A per season.
Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family Aryloxyphenoxypropionate
S-metolachlor (DUAL MAGNUM HERBICIDE EPA# 100-816, SLN#OR-040010)
Oregon
Rate 0.31 to 0.64 lb ai/A (0.33 to 0.67 pints/A Dual Magnum)
Time Apply preemergence at or shortly after planting, but before weeds germinate.
Remarks SLN labels OR-040010 Theses indemnified labels are available only through the Syngenta Indemnified Labels website (https://www.syngenta-us.com/labels/indemnified-label-search). Apply in at least 15 gal/A water with ground equipment; 0.5 inch of rain or irrigation soon after treatment is important to activate herbicide. Use lower rate on coarse soil and higher rate on medium- or fine-textured soils.
Caution Do not mechanically incorporate. Do not apply through any type of irrigation system. Crop may be damaged if excess rain after seeding washes Dual Magnum into the root zone.
Site of action Group 15: very long chain fatty acid synthesis inhibitor
Chemical family Chloroacetamide
phenmedipham (Spin-Aid BELCHIM SPIN-AID HERBICIDE EPA# 264-616-87865)
Rate 0.5 to 1 lb ai/A (3 to 6 pints/A Spin-Aid)
Time Apply any time red beets have four to six true leaves and before weeds have two leaves.
Remarks Avoid applying when daytime weather changes rapidly from cool and cloudy to warm and sunny, or if plants are stressed from insect, disease, or cultivation injury. Tip burn or temporary growth retardation and chlorosis may occur, although plants usually recover within 10 days.
Caution Restricted use due to dermal irritation. Preharvest interval is 45 days. Avoid using more than 7 gal water per quart of herbicide in spray tank; this can cause the herbicide to precipitate.
Site of action Group 5: photosystem II inhibitor
Chemical family Phenylcarbamate
cycloate (Ro-Neet Herbicide EPA# 74530-16, SLN OR-140010)
Rate 2 to 3 lb ai/A (2.7 to 4 pints/A Ro-Neet)
Time Apply preplant to soil dry enough to thoroughly mix; immediately incorporate 2 to 3 inches deep by cross-disking or using a rotary tiller (i.e. within minutes).
Remarks Use on mineral soil only; seed may be planted immediately. SLN OR-140010
Site of action Group 15: very long-chain fatty acid synthesis inhibitor Chemical family Thiocarbamate