Established in Maryland at marsh creeks and rivers on the western and northeastern shores of the Chesapeake Bay, including the Pautuxent River, where it has become the most abundant plant species (M. Naylor, Maryland Dept. of Natural Resources, pers.
(it; has become; the most abundant plant species; L:the Pautuxent River)
it
has become
the most abundant plant species L:the Pautuxent River