Weeds emerge with the emerging crop seedlings and if not controlled in the early stages of crop growth these may cause reduction in yield varying from 10 to 40 per cent depending upon the intensity and kind of weeds present in an area.
Wheat field is generally infested from both dicot and monocot weeds. The moajor dicot weeds are: Chenopodium album (bathua), Fumaria parviflora (gajri), Cirsium arvense (kateli), Anagallis arvensis (Krishna neel), Melilotus alba and Melilotus indica (senji), Bicia sativa (ankri), Lathyrus spp. (chatri marri) etc. Monocot weeds include: Phalaris minor, Avena fatua (wild oat), Polypogon monspliensis, Cyperus rotundus (motha) and Cynodon dactylon (doob).