The lignophytes are vascular land plants that produce robust wood through a cambium. The origin of the cambium, a structure which produces wood and thus girth in a plant, allowed plants to grow into trees on the Earth. During the Devonian radiation, the first woody plants arose on the land in a group called the progymnosperms, and trees have been successful wherever water is plentiful.
Ecology & Form
Plants with xylem produced from a bifacial (2-faced) vascular cambium
The most ancestral lignophyte group are the progymnosperms.