 Without the ideal balance, plant matter may take a long time to break down, drawing nitrogen from other sources, reducing nitrogen availability to existing vegetation which requires it for growth.The risk of dumping garden waste is that it may contain seeds and plant parts that may grow (propagules), as well as increase fire fuel loads, disrupt visual amenity, accrue economic costs associated with the removal of waste as well as costs associated with the mitigation of associated impacts such as weed control, forest fire.There are strong links between weed invasion of natural areas and the proximity and density of housing.