Hornworts are a group of bryophytes, or non-vascular plants. The name refers to the elongated horn-like structure, which is the sporophyte. The flattened, green plant body of a hornwort is the gametophyte plant.
Hornworts may be found world-wide, growing where it is damp or humid. Some species grow in large numbers as tiny weeds in the soil of gardens and cultivated fields. Large tropical species of Dendroceros may be found growing on tree bark.