Columbia subject headings:
Ericaceae--Germany--History.
Ericas--Germany--History.
Gardening--Germany--History.
Heather--Germany--History.
Harvard subject headings:
Ericaceae--Germany--History.
Ericas--Germany--History.
Gardening--Germany--History.
Heather--Germany--History.
Princeton subject headings:
Ericaceae--Germany--History.
Ericas--Germany--History.
Gardening--Germany--History.
Gardens--Germany--History.
Heather--Germany--History.