A vegetative treatment system is a type of wastewater treatment system that uses plants or other living, growing things, such as trees, grasses, and shrubs, to clean water. Wastewater is water that has been used for things like washing dishes, taking showers, and flushing toilets. The plants take in the dirty water and filter out some of the dirt, pollution, and germs that are in it. This helps to clean the water so it can go back into nature and not pollute the environment.