Determination of an appropriate quadrat size and shape for detecting association between plant species

► The outcome of association between species is influenced by the size of quadrat. ► To eliminate this problem, a new method is proposed for determining an appropriate quadrat size. ► This method enables detecting positive, negative and a lack of interspecific association. The outcome of association analysis between species can be influenced by the size and shape of sampling quadrats. To eliminate this problem, a new method is proposed for determining an appropriate size for sampling quadrat. This method is based on measurement of the density of the plant species concerned. The use of this method is illustrated for the detection of association between species in a hypothetical community.