ground cedar vs Christmas green

ground cedar and Christmas green both are nouns.

Word	Noun	Adjective	Verb	Adverb
ground cedar	Yes	No	No	No
Christmas green	Yes	No	No	No

As nouns, Christmas green is a hypernym of ground cedar; that is, Christmas green is a word with a broader meaning than ground cedar:

ground cedar: a variety of club moss, with the common names Creeping Jenny or Northern Running-pine (Lycopodium complanatum)
Christmas green: any of several club mosses having long creeping stems and erect branches

Other hypernyms of ground cedar include ground pine.

ground cedar (noun)	Christmas green (noun)
a procumbent variety of the common juniper	any of several club mosses having long creeping stems and erect branches
a variety of club moss, with the common names Creeping Jenny or Northern Running-pine (Lycopodium complanatum)