Studies were conducted from 1992 to 1995 to determine the effect of rimsulfuron on corn spurry, wild radish, narrowleaf goldenrod, and quackgrass and potato cultivars. Rimsulfuron alone gave 100% control of wild radish, 68 to 70% control of corn spurry, and 75 to 90% control of narrowleaf goldenrod. Rimsulfuron plus metribuzin gave 99 to 100% control of wild radish and 85 to 100% control of corn spurry. Quackgrass control varied from 51 to 90% between experiments, indicating that environmental and plant factors affected the activity of the herbicide. Tank mixes with metribuzin slightly reduced the control of quackgrass but resulted in greater foliar injury than that of rimsulfuron to potato. Slight injury to potato plants disappeared within 2 to 3 wk, and tuber yields were not reduced. Russet Burbank, Shepody, and Kennebec potato cultivars had slight (2 to 8%) injury from rimsulfuron. Injury to Shepody (14 to 20%) and Russet Burbank (11%) increased when rimsulfuron was applied with metribuzin. Rimsulfuron had no effect on the number or the fresh weight of sprouts on daughter tubers tested the next spring after application.
Nomenclature: Metribuzin; rimsulfuron; corn spurry, Spergula arvensis L. #3 SPRAR; narrowleaf goldenrod, Solidago canadensis L. # SOLCA; quackgrass, Elytrigia repens Nevski # AGRRE; wild radish, Raphanus raphanistrum L. # RAPRA; potato, Solanum tuberosum L. # SOLTU ‘Russet Burbank’, ‘Shepody’, ‘Kennebec’.
Additional index words: Daughter tuber sprouting, DPX E-9636.
Abbreviations: GC, ground crack; lf, leaf; PEI, Prince Edward Island; POST, postemergence; PRE, preemergence; RH, relative humidity.