second growth vs forest

second growth and forest both are nouns.

Word	Noun	Adjective	Verb	Adverb
second growth	Yes	No	No	No
forest	Yes	No	Yes	No

As nouns, forest is a hypernym of second growth; that is, forest is a word with a broader meaning than second growth:

second growth: a second growth of trees covering an area where the original stand was destroyed by fire or cutting
forest: the trees and other plants in a large densely wooded area

Other hypernyms of second growth include wood, woods.

second growth (noun)	forest (noun)
a second growth of trees covering an area where the original stand was destroyed by fire or cutting	the trees and other plants in a large densely wooded area
	land that is covered with trees and shrubs

second growth (verb)	forest (verb)
	establish a forest on previously unforested land