productiveness vs fruitfulness

productiveness and fruitfulness both are nouns.

Word	Noun	Adjective	Verb	Adverb
productiveness	Yes	No	No	No
fruitfulness	Yes	No	No	No

As nouns, fruitfulness is a hypernym of productiveness; that is, fruitfulness is a word with a broader meaning than productiveness:

productiveness: the quality of being productive or having the power to produce
fruitfulness: the quality of something that causes or assists healthy growth

Other hypernyms of productiveness include fecundity.

productiveness (noun)	fruitfulness (noun)
the quality of being productive or having the power to produce	the quality of something that causes or assists healthy growth
	the intellectual productivity of a creative imagination