Habitat. The place where a plant naturally grows, as in swamps, in water, upon dry hillsides, etc.
Hybrid. A cross between two species.
Imbricated. Overlapping.
Inflorescence. Mode of disposition of flowers; sometimes applied to the flower-cluster itself.
Involucre. Bracts subtending a flower or a cluster of flowers.
Keeled. Having a central dorsal ridge like the keel of a boat.
Key. A winged fruit; a samara.
Lacerate. Irregularly cleft, as if torn.
Lanceolate. Lance-shaped, broadest above the base, gradually narrowing to the apex.
Leaf. Consisting when botanically complete of a blade, usually flat, a footstalk and two appendages at base of the footstalk; often consisting of blade only.