Vegetative key to the families
Vegetative Key Vegetative key to the families
Submerged plants rooted in mud. Leaves submerged or floating on the surface or sometimes the leaf blades held erect above the water surface. Freshwater or marine (Amphibious plants are not included in this group)
Either; leaves alternate on an elongated stem (sometimes opposite when subtending flowers); or, leaves tufted on a short stem or arising from a rhizome
Leaves pinnatisect (sometimes linear) stem-clasping (Cotula) Asteraceae
Involucral bracts of the female heads or of the outer florets enclosing the fruit(s) at maturity and forming a burr (Fig. 42)
Burr not formed around the fruits at maturity