WEED CONTROL

Herbicide Residue

Sonalan (ethalfluralin), Prowl (pendimethalin), and
Treflan\trifluralin are similar herbicides called
dinitroanilines. Under dry soil conditions these herbicides can
persist in the soil for more than one year. Sonalan has less soil
residue than trifluralin and Prowl. Land treated with Sonalan in
the spring may be planted to any crop the next year except
sugarbeet. Sunflower, soybean, potatoes, and dry edible bean are
quite tolerant of dinitroaniline herbicides. Rotational crop
restrictions for Sonalan, trifluralin or Prowl are found on page
64 of the 1996 North Dakota Weed Control Guide in the table,
"Rotation Restrictions for Crops Grown in North Dakota." The
approximate ranking of other crops from most to least tolerant is
flax, barley, wheat, corn, oat, and sugarbeet.