ironwood tree vs iron-tree

ironwood tree and iron-tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
ironwood tree	Yes	No	No	No
iron-tree	Yes	No	No	No

As nouns, ironwood tree and iron-tree are synonyms defined as:

ironwood tree and iron-tree: a small slow-growing deciduous tree of northern Iran having a low domed shape

Other synonyms of ironwood tree include iron tree, ironwood.

ironwood tree (noun)	iron-tree (noun)
a small slow-growing deciduous tree of northern Iran having a low domed shape	a small slow-growing deciduous tree of northern Iran having a low domed shape
medium-sized hop hornbeam of eastern North America
handsome East Indian evergreen tree often planted as an ornamental for its fragrant white flowers that yield a perfume; source of very heavy hardwood used for railroad ties