Sitka willow vs silky willow

Sitka willow and silky willow both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sitka willow	Yes	No	No	No
silky willow	Yes	No	No	No

As nouns, Sitka willow and silky willow are synonyms defined as:

Sitka willow and silky willow: small shrubby tree of western North America (Alaska to Oregon)

Other synonyms of Sitka willow include Salix sitchensis.

Sitka willow (noun)	silky willow (noun)
small shrubby tree of western North America (Alaska to Oregon)	North American willow with greyish silky pubescent leaves that usually blacken in drying
	small shrubby tree of western North America (Alaska to Oregon)