MtheGM is surely correct, though I've shared Q's interpretation since I first heard the song.

The OED has no definition of "kind" that is anything like "wealth" or "property." "In kind" is an idiomatic phrase which means, more or less, "in precisely or essentially the same way." Hence, if an obligation is settled "in kind," it does mean, in many cases, "by handing over property," but "kind" all by itself is never used as a synonym of "property."

Nineteenth-century database searches turn up no exx. of "lack of kind." Twentieth-century exx. are restricted to printings of Colum's poem. Phrases like "enough kind" meaning "enough property" appear to be nonexistent.

A writer in the Irish University Review in the 1970s noted that "lack of kind," in the poem, was "a phrase unfamiliar to me in Anglo-Irish or English usage."

Colum's "kind" could have been a typo for the archaic (and thus "poetic") "kine," cattle, which would make sense, except that Colum never bothered to correct it in any post-1909 printing - and there were many of them. As it stands, "kind" would be equally "poetic" and has the advantage of rhyming perfectly with "mind."

All the evidence shows that by "lack of kind," Colum meant lack of what the OED defines as "The character or quality derived from birth."