The origin and dissemination of weed seed in container-grown nursery stock

A major problem in container nurseries is weed control. Most weed related research pertains to control of existing weeds with herbicides. In 1983 and 1984, research was conducted to help determine the origin and dissemination of weed seed in nursery container plants. Tests involving the dispersal of weed seed by wind, irrigation water, raindrop splash, and seedpod rupture were conducted. Potting media was also investigated as a possible source of weed seeds. Weed seed dispersal by wind was not a serious problem in this study. Irrigation water was a factor in the dispersal of weed seeds, but the relatively few seeds found prevented this method of dispersal from being significant. Raindrop splash proved to be an important factor in the method of dissemination of weed seeds. The throwing of seeds by Oxalis sp. and a Cruciferae plant proved to be important as the seeds were found 1.2 to 1.8 m from the plant. The infestation of weed seeds in potting media was not serious in this study.