Salix alba vs white willow

Salix alba and white willow both are nouns.

Word	Noun	Adjective	Verb	Adverb
Salix alba	Yes	No	No	No
white willow	Yes	No	No	No

As nouns, Salix alba and white willow are synonyms defined as:

Salix alba and white willow: large willow tree of Eurasia and North Africa having greyish canescent leaves and grey bark

Other synonyms of Salix alba include Huntingdon willow.

Salix alba (noun)	white willow (noun)
large willow tree of Eurasia and North Africa having greyish canescent leaves and grey bark	large willow tree of Eurasia and North Africa having greyish canescent leaves and grey bark