(AR) Archaeophyte
An Archaeophyte
is an established plant believed to have been introduced by man before 1500
AD.
(NE) Neophyte
A Neophyte has been introduced and naturalised after 1500 AD.
(CA) Casual
Alien
A Casual
alien is a plant which grows in an area without being planted but fails to establish
itself in the wild for very long.