water birch vs swamp birch

water birch and swamp birch both are nouns.

Word	Noun	Adjective	Verb	Adverb
water birch	Yes	No	No	No
swamp birch	Yes	No	No	No

As nouns, water birch and swamp birch are synonyms defined as:

water birch and swamp birch: birch of western United States resembling the paper birch but having brownish bark

Other synonyms of water birch include Betula fontinalis, mountain birch, Western birch, Western paper birch.

water birch (noun)	swamp birch (noun)
birch of western United States resembling the paper birch but having brownish bark	birch of western United States resembling the paper birch but having brownish bark