Sphagnum also been used to preserve food. Up to 2000-year-old containers of butter or lard have been found. "Sphagnum" moss has also been used for centuries as a dressing for wounds, including through World War I. Since it is absorptive and extremely acidic, it inhibits growth of bacteria and fungi, so it is used for shipping seeds and live plants. Peat moss is used to dispose of the clarified liquid output (effluent) from septic tanks in areas that lack the proper conditions for ordinary disposal means. It is also used as an environmentally friendly alternative to chlorine in swimming pool sanitation.
Plant cover Plant cover The abundances of plant species are often measured by plant cover, which is the relative area covered by different plant species in a small plot. Plant cover is not biased by the size and distributions of individuals, and is an important and often measured characteristic of the composition of plant communities. Plant cover data may be used to classify the studied plant community into a vegetation type, to test different ecological hypothesis on plant abundance, and in gradient studies, where the effects of different environmental gradients on the abundance of specific plant species are investigated. The most common