silky willow vs Salix sitchensis

silky willow and Salix sitchensis both are nouns.

Word	Noun	Adjective	Verb	Adverb
silky willow	Yes	No	No	No
Salix sitchensis	Yes	No	No	No

As nouns, silky willow and Salix sitchensis are synonyms defined as:

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

Other synonyms of silky willow include Sitka willow.

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