harvest vs haying

harvest and haying both are nouns.

Word	Noun	Adjective	Verb	Adverb
harvest	Yes	No	Yes	No
haying	Yes	No	No	No

As nouns, haying is a hyponym of harvest; that is, haying is a word with a more specific, narrower meaning than harvest:

harvest (noun)	haying (noun)
the season for gathering crops	the season for cutting and drying and storing grass as fodder
the gathering of a ripened crop	the harvesting of hay
the consequence of an effort or activity
the yield from plants in a single growing season

harvest (verb)	haying (verb)
remove from a culture or a living or dead body, as for the purposes of transplantation
gather, as of natural products