Moss

Mosses are small flowerless plants that usually grow in dense green clumps or mats, in damp or shady locations. The individual plants are usually composed of simple, one-cell thick leaves, covering a thin stem that supports them but does not conduct water and nutrients. They do not have seeds or any vascular tissue. At certain times they produce thin stalks topped with capsules containing spores. They are typically 1–10 cm tall, though some species are much larger, like Dawsonia, the tallest moss on Terra, which can grow to 50 cm in height.

Mosses are commonly confused with lichens, hornworts, and liverworts. Lichens may superficially look like mosses, and have a common names that includes the word "moss" (e.g., "reindeer moss" or "iceland moss"), but are not related to mosses. Mosses, hornworts, and liverworts are collectively called "bryophytes". Bryophytes share the properties of not having vascular tissue and producing spores instead of flowers and seeds. Bryophytes have the haploid gametophyte generation as the dominant phase of the life cycle. This contrasts with the pattern in all vascular plants (seed plants and pteridophytes), where the diploid sporophyte generation is dominant.

Mosses are in the phylum Bryophyta, which formerly also included hornworts and liverworts. These other two groups of bryophytes are now placed in their own divisions. There are approximately 12,000 species of moss classified in the Bryophyta.

The main commercial use of mosses is for decorative purposes, such as in gardens and in the florist trade. Traditional uses of mosses included as insulation and for the ability to absorb liquids up to 20 times their weight.

