in Thoreau’s Journal:

I must not forget the lichen-painted boles of the beeches. So round even to the red-bridge.

Where the red-maple buds are already much expanded—foretelling summer—though our eyes see only winter as yet— As I sit under their boughs looking into the sky—I suddenly see the myriad black dots of the expanded buds against the sky—

Their sap is flowing. The elm buds too I find are expanded though on earth are no signs of spring.