western tamarack vs larch

western tamarack and larch both are nouns.

Word	Noun	Adjective	Verb	Adverb
western tamarack	Yes	No	No	No
larch	Yes	No	No	No

As nouns, larch is a hypernym of western tamarack; that is, larch is a word with a broader meaning than western tamarack:

western tamarack: tall larch of western North America have pale green sharply pointed leaves and oblong cones; an important timber tree
larch: any of numerous conifers of the genus Larix all having deciduous needlelike leaves

Other hypernyms of western tamarack include larch tree.

western tamarack (noun)	larch (noun)
tall larch of western North America have pale green sharply pointed leaves and oblong cones; an important timber tree	any of numerous conifers of the genus Larix all having deciduous needlelike leaves
	wood of a larch tree