Plate from 18th century encyclopedia showing genera of mosses including: byssi, confervae, tremellae, usneae, coralloides, lichenoides, mnium and sphagnum. Botanically, mosses are non-vascular plants in the land plant division Bryophyta. They are small (a few centimeters tall) herbaceous (non-woody) plants that absorb water and nutrients mainly through their leaves and harvest sunlight to create food by photosynthesis. They differ from vascular plants in lacking water-bearing xylem tracheids or vessels. Mosses reproduce using spores, not seeds and have no flowers.