Arrest®

             OTHER NAMES

·        Agricultural products:  Poast®, Poast Plus®, Vantage®

·        Common/generic name:  sethoxydim

             HISTORY

·        Discovered by Nippon Soda in late 1970’s, developed by BASF

·        First registered on soybean and cotton in early 1980’s, later registered on peanut, forage legumes, and numerous vegetable crops

·        The first of a large group of postemergence herbicides that selectively controls grasses in broadleaf crops

·        Arguably, a land-mark herbicide in American agriculture

             HERBICIDAL ACTIVITY

·        Very specific, narrowly focused mode of action

·        Inhibits an enzyme critical in plant’s fatty acid synthesis and thus cell growth

·        Symptoms are slow to be expressed

o       Growth of grasses ceases in 2 days

o       Obvious symptoms take 1-2 weeks to develop

·        Broadleaf plants are not affected by Arrest®, since the enzyme in broadleaf plants is less sensitive to inhibition than the same enzyme in grasses.  Some grasses are tolerant of Arrest® and these grasses rapidly detoxify the herbicide.

              BEHAVIOR IN PLANTS

·        Quickly absorbed by plant foliage (rain-fast after 1 hour)

·        Actively translocated throughout the grass plants, where it accumulates in the growing points of foliage and roots (important for perennial grass control)

              BEHAVIOR IN SOILS

·        No significant activity in the soil

·        Rapidly degraded

WEED CONTROL IN FORAGE LEGUMES

·        Arrest is for postemergence control of annual and perennial grasses

·        Weed size is the critical factor for determining when to spray Arrest®

o       Smaller grasses are more effectively controlled than larger grasses, although there is more margin for error with Arrest® than other herbicides (for example Slay®)

·        Weeds should be actively growing at time of treatment

o       Avoid spraying during drought, temperature extremes, or immediately before or after mowing

·        Rate:  2¼ - 3¾ pt./A (or 1½ - 2¼% Arrest® solution in water for hand-sprayer)

·        Two applications, one month apart, will likely be needed for perennial grass control (johnsongrass, bermudagrass, quackgrass, etc.)

            ADJUVANTS, ETC.

·        Arrest® and Vantage® labels are written with high rates and no adjuvant requirements

·        Other sethoxydim herbicides require the use of a crop oil concentrate and their herbicide rates are correspondingly lower

·        Always follow the herbicide label for adjuvant recommendations

CROP ROTATION/FUTURE PLANTINGS

·        No crop rotation restrictions

             MISCELLANEOUS

·        Arrest® will control most grass species; including grass crops - wheat, rye, oats, barley, ryegrass, grain sorghum (milo), and corn.

·        Perennial grasses are difficult to control with Arrest®.  Multiple applications will be needed.  Tillage between forage plantings will help weaken the perennial grasses and improve control with Arrest®.

·        Do not tank-mix Arrest® with other herbicides.  The Arrest® molecule is fragile and is less effective when combined with other herbicides compared to separate herbicide applications.  Separate herbicide applications by at least 3 days.