Larix lyallii vs larch tree

Larix lyallii and larch tree both are nouns.

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

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

Larix lyallii: medium-sized larch of the Rocky Mountains; closely related to Larix occidentalis
larch tree: any of numerous conifers of the genus Larix all having deciduous needlelike leaves

Other hypernyms of Larix lyallii include larch.

Larix lyallii (noun)	larch tree (noun)
medium-sized larch of the Rocky Mountains; closely related to Larix occidentalis	any of numerous conifers of the genus Larix all having deciduous needlelike leaves