field-pea plant vs Austrian winter pea

field-pea plant and Austrian winter pea both are nouns.

Word	Noun	Adjective	Verb	Adverb
field-pea plant	Yes	No	No	No
Austrian winter pea	Yes	No	No	No

As nouns, field-pea plant and Austrian winter pea are synonyms defined as:

field-pea plant and Austrian winter pea: variety of pea plant native to the Mediterranean region and North Africa and widely grown especially for forage

Other synonyms of field-pea plant include field pea, Pisum arvense, Pisum sativum arvense.

field-pea plant (noun)	Austrian winter pea (noun)
variety of pea plant native to the Mediterranean region and North Africa and widely grown especially for forage	variety of pea plant native to the Mediterranean region and North Africa and widely grown especially for forage