The young aspens are the first of indigenous trees conspicuously leafed.

May 2.

May 2,, 1855

P. M. — By boat up Assabet. 

Quince begins to leaf, and pear; perhaps some of last earlier. 

Aspen leaves of young trees —or twenty to twenty-five feet high—an inch long suddenly; say yesterday began; not till the 11th last year. Leafing, then, is differently affected by the season from flowering. The leafing is apparently comparatively earlier this year than the flowering. The young aspens are the first of indigenous trees conspicuously leafed.

Diervilla, say began to leaf with viburnums. 

Amelanchier Botryapium yesterday leafed. 

That small native willow now in flower, or say yesterday, just before leaf, —for the first seem to be bracts, — two to seven or eight feet high, very slender and curving. Apparently has three or four lanceolate toothed bracts at base of petioled catkin; male three quarters and female one inch long; scales black and silky-haired; ovary oblong-oval, stalked, downy, with a small yellowish gland not so long as its stalk. See leaf by and by. 

Saw many crow blackbirds day before yesterday. 

Vigorous look the little spots of triangular sedge (?) springing up on the river-banks, five or six inches high, yellowish below, glaucous and hoary atop, straight and rigid. 

Many clamshells have round brassy-colored spots as big as a fourpence. Found one opened by rats last winter, almost entirely the color of tarnished brass within. 

Open the Assabet spring. 

The anemone is well named, for see now the nemorosa, amid the fallen brush and leaves, trembling in the wind, so fragile. 

Hellebore seems a little later than the cabbage. 

Was that a harrier seen at first skimming low then seating and circling, with a broad whiteness on the wings beneath?

H. D. Thoreau, Journal, May 2, 1855

Aspen are the first trees to leaf.  . . .  See May 2, 1859 (" I am surprised by the tender yellowish green of the aspen leaf just expanded suddenly, even like a fire, seen in the sun, against the dark-brown twigs of the wood, though these leafets are yet but thinly dispersed. It is very enlivening."); May 17, 1860    ("Standing in the meadow near the early aspen at the island, I hear the first fluttering of leaves, - a peculiar sound, at first unaccountable to me.") See also  A Book of Seasons,   Aspens.