Ambrosia psilostachya vs western ragweed

Ambrosia psilostachya and western ragweed both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ambrosia psilostachya	Yes	No	No	No
western ragweed	Yes	No	No	No

As nouns, Ambrosia psilostachya and western ragweed are synonyms defined as:

Ambrosia psilostachya and western ragweed: coarse perennial ragweed with creeping roots of dry barren lands of southwestern United States and Mexico

Other synonyms of Ambrosia psilostachya include perennial ragweed.

Ambrosia psilostachya (noun)	western ragweed (noun)
coarse perennial ragweed with creeping roots of dry barren lands of southwestern United States and Mexico	coarse perennial ragweed with creeping roots of dry barren lands of southwestern United States and Mexico