Defeated again. Online, at last, at Hathitrust digital collections, I had free open access to the book of poems, "Ubhla de 'n Craoibh." Went through the book, cover to cover.

No humming of the bees -- maybe two dozen other poems, but not that poem.

So I am still hunting for a proper edition copy of the poem that begins

"is aoibhinn crónán na mbeach bhfiadain"

which speaks of

"the delightful humming of the bees in their nest in the field"