National Agricultural Research Centre, Pakistan Agricultural Research Council, Islamabad
Generally, the weed count data exhibit significant spatial variations. Adequate sampling procedures nerd to be developed for acquiring true representation of weed flora. An experiment was conducted to determine optimum quadrat size and quadrat number for weed species count in transplanted rice. Characteristic curves both for species area and quadrat number first increased abrupily and then levelled off as fewer species were added with an increase either in the quadrat size or quadrat number. It was determined that at least two quadrats each of 0.1875m2 were needed to adequately represent the weed community.
