Weeds are plants that invade areas where they do not belong. They destroy original ecosystems, damage health and restrict optimum usage of land. They often spread from backyards when people dump garden clippings onto road reserves, vacant land or near bushland. Birds and animals carry them on their fur so they need to be inhibited as much as possible. Fragments of weeds – bulbs, roots, tubers, seeds, spores – more adapted to the artificially enriched soils of urban areas than native plants, sprout easily, and outcompete the original ecosystem. Native bushland is smothered. When the weeds decay they increase soil and water nutrient load. When they die they build up a fuel load and there is greater threat from fire in many cases. They threaten the very existence of wildlife that is already endangered, plant and animal. Plant pathogens (diseases) can also destroy native ecosystems.