piece of ground vs tract

piece of ground and tract both are nouns.

Word	Noun	Adjective	Verb	Adverb
piece of ground	Yes	No	No	No
tract	Yes	No	No	No

As nouns, piece of ground and tract are synonyms defined as:

Other synonyms of piece of ground include parcel, parcel of land, piece of land.

piece of ground (noun)	tract (noun)
an extended area of land	a bundle of myelinated nerve fibers following a path through the brain
	a system of body parts that together serve some particular purpose
	a brief treatise on a subject of interest; published in the form of a booklet
	an extended area of land