curlycup gumweed vs gum plant

curlycup gumweed and gum plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
curlycup gumweed	Yes	No	No	No
gum plant	Yes	No	No	No

As nouns, gum plant is a hypernym of curlycup gumweed; that is, gum plant is a word with a broader meaning than curlycup gumweed:

curlycup gumweed: perennial gumweed of western and central North America
gum plant: any of various western American plants of the genus Grindelia having resinous leaves and stems formerly used medicinally; often poisonous to livestock

Other hypernyms of curlycup gumweed include gumweed, rosinweed, tarweed.

curlycup gumweed (noun)	gum plant (noun)
perennial gumweed of western and central North America	any of various western American plants of the genus Grindelia having resinous leaves and stems formerly used medicinally; often poisonous to livestock