Alpine to subalpine plant:
Plants found growing at high elevations or at far northern (or far southern) latitudes, above, at, or only slightly below tree line, and extending to the permanent show and ice cover. Regrettably, the alpine flora of Hawaii is only superficially represented within the Synthesis. I welcome any additional input to make the list more complete for that area.
Aquatic plant:
Plants that at maturity and under normal water levels grow submerged or floating on the water surface, but not emerging substantially above the water surface.
Floating plant:
Aquatic plants that at maturity and under normal water levels grow completely free floating on the water surface, or have their leaves floating on the water surface.
Submerged plant:
Aquatic plants that at maturity and under normal water levels produce their stems and leaves principally under water.
Wetland plant:
Plants growing in aquatic or wetland habitats. These include all known floating, submerged, and emergent taxa, plus those that are found in permanently or seasonally wet habitats.
Note: Species of wetland plants as here presented are not necessarily those designated as wetland plants by the U.S. Fish and Wildlife Service.
Epiphytic/hemi-epiphytic plant:
Non-parasitic plants that grow exclusively upon and are anchored to other plants.