Tillage plus trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) and prometryn [2,4-bis (isopropylamino)-6-(methylthio)-s-triazine] and tillage plus trifluralin and fluometuron [1,1-dimethyl-3-(α,α,α-trifluoro-m-tolyl)urea] applied as soil-incorporated preplanting treatments were compared with tillage alone in cotton (Gossypium hirsutum L.) grown in 51-cm and 102-cm rows on fine sandy loam soil. Over 3 yr, cotton grown in 51-cm rows yielded 15% more than cotton grown in 102-cm rows. Final cotton emergence was not altered by weed-control treatment or by planting pattern. Weed-control treatments with herbicides provided essentially complete, season-long control of grass and broadleaf weeds. At cotton layby, more weeds were in no-herbicide plots with 51-cm rows compared with 102-cm rows, but at cotton harvest numbers of weeds in both row patterns were essentially equal.
