Black frost

September 28

Butternuts still on tree and falling, as all September. 

September 28, 2020

This morning we had a very severe frost, the first to kill our vines, etc., in garden; what you may call a black frost, - making things look black. Also ice under pump.

H. D. Thoreau, Journal, September 28, 1860

Butternuts still on tree and falling, as all September. See September 19, 1859 ("Butternuts have been falling for two or three weeks, — now mostly fallen, — but must dry and lose their outer shells before cracking them.")

A very severe frost . . .ice under pump. See September 15, 1851 ("Ice in the pail under the pump, and quite a frost.") See also September 29, 1860 ("Another hard frost and a very cold day."): September 30, 1860 ("Frost and ice."); October 1, 1860 (“Remarkable frost and ice this morning")