Some pollutants, such as heavy metals, are not often readily treated by bioremediation techniques. In such cases, phytoremediation may be useful. Phytoremediation relies on the introduction of certain plants that are capable of absorbing a pollutant and concentrating it in the above-ground portion of the plant, which can then be removed. The pollutant-containing plants can then be destroyed in an incinerator to concentrate the pollutants even more, or, in some cases, the pollutants can even be recycled for additional use.