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The present study was designed to investigate the demographic patterns of Cleome viscosa L., which is the common summer annual of Sindh desert. Demographic studies were carried out at two site named as site ’A’ and site ’B’. Plants exhibited Deveey type I survivorship curves, characteristic of annuals. Populations of C. viscosa were found to be highly dynamic on spatial scale. Soil moisture content, competition and grazing were some of the factors responsible for the considerable variations in the plant density and growth of plants. Plants inhabiting site ’B; exhibited better vegetative and reproductive growth due to greater amounts of soil nutrients and high water holding capacity of the soil (thereby providing better soil moisture regime). C. viscosa at both the sites possessed persistent seed bank. The below ground seed bank was much diverse than the above ground vegetation. C. viscosa produced light weighted seeds in large numbers. Wind is the predominant agent for the dispersal of seeds. Seeds traveled grater distances mainly due to their lighter weights and taller mother plants.