Larix russica vs larch tree

Larix russica and larch tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
Larix russica	Yes	No	No	No
larch tree	Yes	No	No	No

As nouns, larch tree is a hypernym of Larix russica; that is, larch tree is a word with a broader meaning than Larix russica:

Larix russica: medium-sized larch of northeastern Russia and Siberia having narrowly conic crown and soft narrow bright-green leaves; used in cultivation
larch tree: any of numerous conifers of the genus Larix all having deciduous needlelike leaves

Other hypernyms of Larix russica include larch.

Larix russica (noun)	larch tree (noun)
medium-sized larch of northeastern Russia and Siberia having narrowly conic crown and soft narrow bright-green leaves; used in cultivation	any of numerous conifers of the genus Larix all having deciduous needlelike leaves