moss

Botanically, mosses are bryophytes, or non-vascular plants. They differ from 'higher' plants by not having internal water-bearing vessels or veins, and no flowers and therefore no fruits, cones or seeds. They are small (a few centimeters tall) and herbaceous (nonwoody) and absorb water and nutrients through their leaves. Mosses have stems which may be simple or branched and upright or lax, simple leaves that often have midribs, roots (rhizoids) that anchor them to their substrate, and spore-bearing capsules on long stems. They harvest sunlight to create food through photosynthesis.[3][4] Mosses do not absorb water or nutrients from their substrate through their roots, so while mosses often grow on trees, they are never parasitic on the tree.