Abstract:Based on the survey sampling far from the parent plants, the quantitative analysis on seed dispersal of Hordeum brevisubulatum (Trin.)Link on alkalized meadow in the Songnen Plain of China on six orientations was conducted. The results showed that due to the effect of wind direction, the greatest number of seeds disposed was in the northeast, which was 4 times more than the smallest number in the South west. The mean radius of the seed dispersal was about 130 cm. All seed disposal patterns per unit area in different orientations fit, more or less, well with the weibull distribution. It refected that seed dispersal of the with barley provided the character of extending, far from the parent plants, their potential space niche under the natural conditions at the Songnen Plain. The number of seeds dispersed by sequence centrifugation far from the parent plants increased following a Logistic curve relevant to the expansion of accumulated unit area. The rates of increase were relatively lower in the east and northeast where seed disporsal was greater and the distance was farther from the parent plants.