Lactuca sativa crispa vs loose-leaf lettuce

Lactuca sativa crispa and loose-leaf lettuce both are nouns.

Word	Noun	Adjective	Verb	Adverb
Lactuca sativa crispa	Yes	No	No	No
loose-leaf lettuce	Yes	No	No	No

Lactuca sativa crispa (noun)	loose-leaf lettuce (noun)
distinguished by leaves having curled or incised leaves forming a loose rosette that does not develop into a compact head	lettuce with loosely curled leaves that do not form a compact head