clopyralid (Stinger)
Idaho and Oregon only
Rate 0.094 to 0.187 lb ae/A (0.25 to 0.5 pints/A Stinger)
Time Apply in 10 gal or more total spray volume when seed crop has at least two true leaves.
Remarks SLN labels ID-170008 and OR-120010. See label for use rates for control of certain broadleaf weeds and Canada thistle suppression. One or two broadcast applications are allowed, not to exceed 0.5 pints/A per year.
Caution For Canada thistle, apply after most thistle basal leaves emerge but before buds form, at least 30 days prior to harvest. Apply once or twice, but do not exceed 0.5 pints/A Stinger per growing season. Radish crops are more susceptible to herbicide injury during bolting and/or flowering; use the lower rate during that time. Crop safety data are limited; use only when crop injury is acceptable. Follow rotational crop restrictions on label. Avoid spray drift to sensitive crops. Do not use any part of the treated field, including seed, seed screenings, hay forage, and stubble, for human or animal consumption.
Site of action Group 4: synthetic auxin
Chemical family Pyridine
diquat (Reglone)
see Preharvest Desiccation at end of this section
fluroxypyr (Starane)
Oregon only
Rate 0.11 to 0.14 lb ae/A (4.8 to 6.4 oz/A)
Time Apply broadcast to actively growing broadleaf weeds with 2 to 4 true leaves.
Remarks SLN OR-200009. Controls nightshades, buckwheat, mustards, pigweed. REI 24 hr. PHI 14 days. Rainfast in 1 hr. Tankmixes with clopyralid are very effective. Use lower rates of both products if tankmixing to reduce potential of injury and carryover from clopyralid (Stinger).
Caution Some short-term crop stunting possible. Do not add a spray adjuvant because selectivity may be compromised.
Site of action Group 4: synthetic auxin
Chemical family Pyridine
quizalofop (Assure II)
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 or exceed 25 oz/A per season.
Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family Aryloxyphenoxypropionate
simazine (Simazine 4L)
Oregon only; fall planted radish only
Rate 0.8 to 1 lb ai/A (1.6 to 2 pints/A Simazine)
Time Apply in fall after radish plants are well established and after winter rains begin, but before most winter weeds emerge. A second application can be made in the spring just after the last cultivation.
Remarks SLN label OR-090014. Use a minimum of 20 gal spray solution with ground equipment per acre. For best results, field will have been cultivated one or more times and be relatively weed-free at time of treatment. Irrigation is not required to activate the herbicide if adequate rainfall is received.
Caution Do not use on sandy, loamy, or gravelly areas of fields, or where water pools. Avoid crop rotations to susceptible crops. Do not use crop, crop residues, or seed screenings for food or feed. Do not apply through any type of irrigation system.
Site of action Group 5: photosystem II inhibitor
Chemical family Triazine
S-metolachlor (Dual Magnum)
Rate Use 1.0 to 1.33 pints/A (0.95to 1.27 lb ai/A)
Time Broadcast and incorporate before direct-seeding or transplanting. Or apply within 48 hours after transplanting.
Remarks SLN labels ID-150006, OR-040010, and WA-990005. SLN OR-060012 allows post-plant surface applications, Indemnified label.
Caution Restricted-use herbicide in Washington to protect surface and groundwater. WA SLN excludes Diakon radish. Crop may be injured if environmental conditions are unfavorable. Do not feed or graze radish forage or fodder or cut for hay or forage. No part of treated field, including seed, seed screenings, hay, forage, or stubble, may be for human or animal consumption. See label for all other precautions and regulations.
Site of action Group 15: Inhibits very long chain fatty acid synthesis
Chemical family Chloroacetamide