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Peak® 75WG Herbicide

Peak® 75WG herbicide is a water dispersible granular herbicide for selective post-emergent control of broadleaf weeds in field corn and winter wheat. Peak 75WG contains the active ingredient prosulfuron, a group 2 mode of action herbicide that controls broadleaf weeds.

PMRA Reg. No. 25310. Always read and follow label directions.




Group 2 herbicide


Thorough coverage of the weeds is essential for effective control with the Peak 75WG herbicide tank mixes. Peak 75WG herbicide is absorbed through the leaves and is rapidly translocated to the plant's growing points. Depending on the weed species and growing conditions, visual symptoms of dying weeds (discolouration) take 1 - 3 weeks to appear. Symptoms are first visible in the youngest tissues. Death of plants usually occurs 2 - 4 weeks after application.


Controlled: Lady's thumb, Lamb's-quarters, Wild mustard, Redroot pigweed, Common ragweed, Cocklebur (controlled with Banvel II tank-mix)

Suppressed: Wild buckwheat, Velvetleaf (for complete list of crops and diseases controlled, please see product label)


5.4 g/ac (13.3 g/ha). 1 jug of 270 g treats 50 acres


Minimum 15 gal/ac (150 L/ha). For product in water soluble bags: Do not use liquid fertilizer as a carrier for Peak 75WG Herbicide applications. Liquid fertilizer may prevent the water-soluble bags from dissolving properly.




For broadleaf weed control, Peak 75WG herbicide MUST be used only in tank mix with one of the following herbicides:

  • Field Corn - Banvel® II herbicide or Banvel® Dry EG herbicide
  • Seed Corn - Banvel® II herbicide
  • Winter Wheat - Pardner® herbicide

Peak 75WG can also be tank mixed with glyphosate in glyphosate-tolerant field corn (as permitted by the PMRA tank mix policy of unlabelled tank mixes).

Field Corn: Apply Peak 75WG herbicide as a broadcast spray, with Banvel II herbicide or Banvel Dry EG herbicide and a recommended surfactant, to field corn betweent he two and seven leaf stages.

Seed Corn: Apply Peak 75WG herbicide as a broadcast spray, with Banvel II herbicide and a recommended surfactant, to seed corn between the two and seven leaf stages.

Winter Wheat: Apply Peak 75WG herbicide as a broadcast spray, with Pardner herbicide and a recommended surfactant, to wheat up-to and including BBCH Growth Stage 32 (beginning of stem elongation).

For optimum results, apply ot actively growing weeds when they are in the one to six leaf stage. Please refer to prodcut label for detailed application instructions.


4 hours


Corn forage and grazing: 60 days

Corn grain: 120 days

Winter wheat forage and grazing: 45 days

Winter wheat grain: 75 days


12 hours


For maximum crop safety, do not apply Peak 75WG Herbicide to corn which has been treated with an organophosphorus insecticide. If an IR corn hybird is planted, organophosphorus insecticides can be used according to label directions without increasing the likelihood of injury to those hybrids when Peak 75WG herbicide is applied.


For resistance management, Peak 75WG herbicide is a Group 2 herbicide. Any weed population may contain or develop plants naturally resistant to Peak 75WG and other Group 2 herbicides. The resistant biotypes may dominate the weed population if these herbicides are used repeatedly in the same field. Other resistance mechanisms that are not linked to site of action, but specific for individual chemicals, such as enhanced metabolism, may also exist. Appropriate resistance-management strategies should be followed. To delay herbicide resistance: Where possible, rotate the use of Peak 75WG herbicide or other Group 2 herbicides with different herbicide groups that control the same weeds in a field. Use tank mixtures with herbicides from a different group when such use is permitted.


  • Do not apply Peak 75WG to winter wheat if cold, wet environmental conditions that stress wheat are expected within 1 week after application. Cold, wet weather following Peak 75WG applications to winter wheat may result in injury to the cereal crop; this injury is normally temporary and yields are not affected.
  • Under unfavourable environmental conditions such as drought, heat, flooding, prolonged cool temperatures or insufficient fertility, adequate control may not be achieved and re-growth may occur.