Mosses are tiny, non-vascular, flowerless plants in the group Bryophyta that usually form soft green carpets or cushions on damp soil, rocks, wood, or tree trunks. They lack true roots, stems, and leaves, instead using simple leaf-like structures and fine rhizoids to absorb water and nutrients directly from their surroundings, which is why they thrive in moist, shaded environments.
Spike or club mosses are small, moss-like vascular plants in the genus Selaginella that form low, creeping mats or tufted clumps with tiny, scale-like leaves along branched stems. Despite the name, they are not true mosses (which are non-vascular); instead, they are ancient, fern relatives that reproduce by spores produced in little cones or “spikes” at the tips of their branches.