Turns out MD has a pretty decent site about native plants and invasive plants too. I like both.
Maryland Native Plant Society
'The Alliance for the Chesapeake Bay is a regional nonprofit organization that builds and fosters partnerships for the restoration of the Bay and its rivers.
We [act as] a facilitator of Bay issues and a source of objective, in-depth information on the Bay restoration. The Alliance does not lobby or litigate, but brings together diverse interests in search of cooperative solutions to Bay problems.' From ACB's Mission statement.
Alliance for the Chesapeake Bay