Prunus besseyi vs subshrub

Prunus besseyi and subshrub both are nouns.

Word	Noun	Adjective	Verb	Adverb
Prunus besseyi	Yes	No	No	No
subshrub	Yes	No	No	No

As nouns, subshrub is a hypernym of Prunus besseyi; that is, subshrub is a word with a broader meaning than Prunus besseyi:

Prunus besseyi: dwarf ornamental shrub of western United States having large black to red and yellow sweet edible fruit
subshrub: low-growing woody shrub or perennial with woody base

Other hypernyms of Prunus besseyi include suffrutex.

Prunus besseyi (noun)	subshrub (noun)
dwarf ornamental shrub of western United States having large black to red and yellow sweet edible fruit	low-growing woody shrub or perennial with woody base