'Tis not that Dying hurts us so — Slaves

'Tis not that Dying hurts us so- 1
'Tis Living-hurts us more-
But Dying-is a different way-
A kind behind the Door-

The Southern Custom-of the Bird- 5
That ere the Frosts are due-
Accepts a better Latitude-
We-are the Birds-that stay.

The Shrivers round Farmers' doors- 9
For whose reluctant Crumb-
We stipulate-till pitying Snows
Persuade our Feathers Home.
(F.528/J.335)
[1] us:: slaves.
[4] kind:: birth, origin (OED n.1), race (white or black); a kind manner.
[5] behind the door:: hard to reach; cheating. “They say when a man will be rich, he must set his soul behind the door; that is to say, he must use falsehood and deceit.”—Sermons and Remains of Hugh Latimer (1845) by George Elwes Corrie.
[5] Bird:: a bird of passage; a guy; an immigrant.
[5] Southern Custom:: a hint of this riddle together with Farmers in line 9.
[6] Frosts:: cold, frigid acts against slaves.
[7] Latitude:: a free space.
[8] We, Birds, stay:: slaves living in the frigid environment.
[9] Shiverer:: one who breaks (something) into small pieces (OED 1).
[9] Farmers:: rustics.
[10] stipulate:: to contract, make a bargain.
[11] snow:: the white hair of age (OED 6a).
[12] feather:: anything of little strength or importance (OED 10b).

They were for the most part slaves in Africa—they were bought as slaves, brought here as slaves, sold here as slaves, and held as slaves, long before any enactment made them slaves. . . . Our blacks compose one half of the population of the southern states. ─ Encyclopaedia of the Trade and Commerce of the United States (1854) By James Dunwoody Brownson De Bow