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Active materials

Peak is a selective herbicide applied after emergence of both crop and weeds for the control of broadleaf weeds in field corn, grain sorghum, winter wheat, spring wheat, barley, rye, oats, triticale, proso millet, and postemergence to weeds following small grain harvest. In addition, preemergence applications can be used in some areas for broadleaf weed control in sorghum. Peak is a water-dispersible granule formulation which must be thoroughly mixed in water and applied as a spray.
Refer to Tables 1 and 5 for a listing of weeds controlled when Peak is applied postemergence. The degree of weed control resulting from application of Peak is dependent upon weed species, weed size at application, rate of Peak applied, and growing conditions. Weed control is optimum when ample soil moisture exists and weeds are actively growing.
Peak provides control or partial control of many broadleaf weeds. When reference is made to weeds partially controlled, this means that Peak provides significant weed control activity, but not always at a level generally considered acceptable for commercial weed control. Peak does not control grass weeds; therefore, if grasses are expected, a grass herbicide (such as Dual II Magnum®, or Bicep Lite II Magnum preemergence in sorghum) should be applied.
Throughout this label, where rate ranges are listed, use the lower rate of Peak when weeds are in the middle or shorter portion of the recommended size range and the infestation is light or moderate. Use a higher rate of Peak when weeds are in the taller portion of the recommended size range or the infestation is heavy, and when a longer duration of weed control is desired.
Growth of susceptible weeds is inhibited soon after application of Peak. The leaves of susceptible plants turn yellow, red, or brown after several days, followed by death of the growing point. Complete plant death occurs 1-3 weeks after application, depending upon weed species and growing conditions. Weeds not completely killed by Peak are often stunted and are less competitive to the crop. Following postemergence applications, Peak provides residual/soil activity for up to 4 weeks.
This herbicide controls weeds by inhibiting a biochemical process which produces certain essential amino acids necessary for plant growth. The inhibited enzyme system is acetolactate synthase (ALS). Occurrence of ALS-resistant weed biotypes can be prevented or delayed by using this product in tank mixtures or in sequence with other herbicides having a different mode of action, and by using some form of mechanical control or a herbicide with a different mode of action to control weed escapes before they set seed.
Peak applied in accordance with this label rarely causes crop injury. When injury occurs, it is generally of short duration and yield potential is not affected.
Restrictions: To avoid possible illegal residues: (1) Do not graze or feed forage from Peak-treated crops to livestock until 30 days after application. (2) Do not harvest silage until 40 days after application. (3) Do not harvest grain until 60 days after application. (4) Do not apply more than 1 oz/A of Peak in the cropping season. (5) Complete all Peak applications before sorghum exceeds 30 inches in height or before head emergence; or before small grain cereal crops have the second node detectable in stem elongation. Do not use Peak in the San Luis Valley of CO. In WA, abide by all sulfonylurea aerial application rulings in effect by the Washington Department of Agriculture.

Important: Always read and follow label instructions when buying or using this product.

Registered for cultures
Winter wheat
Spring wheat
Spring barley
Winter barley
Winter rye
Spring rye
Spring oats
Winter oats
Winter triticale
Spring triticale