Not in Lighter, "Historical Dictionary of American Slang." Many slang uses of huckleberry, but not that one.

To me, those quotations sound like there has been more than one use.

When the huckleberries were ripe, we would go into the bush and gather them, with accompanying picnic, but the quotations, other than those from Woodworth and Moulton, suggest other meanings.

(Huckleberry train- one that stops at every station. From Lighter's Dictionary.)