Sixty-nine weed species belonging to 25 families and 58 genera were found in Kumber Cotton Farm, Bardiya, Western Nepal. The dominant families were the Poaceae (13 species), Asteraceae (10 spp.), Cyperaceae (6 spp.) and Fabaceae (5 spp.). The average population of crop and weeds per sq m were 7.7 and 703.5, respectively, indicating one cotton plant competes with 91.36 weeds of 17 different kinds. The topmost five weeds with higher IVI value in cotton ecosystem included Eragrosris renella (55.82). Cynodon dactylon (44.45), Cyperus compressus (31.26). Cyperus rotundus (25.09) and Dactylocrenium aegyprium. The most frequent weeds having 80–100% F were: Cyperus rorundus (100), Cyperus compressus (100), Dacryloctenium aegyptium (90), Murdannia nudiflora (90), Cynodon dacrylon (90) and Ageratum houstonianum (90).
