Invasive species

August  19. 

Examine now more at length that smooth, turnip-scented brassica which is a pest in some grain-fields. Formerly in Stow’s land; this year in Warren’s, on the Walden road. To-day I see it in Minot Pratt’s, with the wild radish, which is a paler yellow and a rougher plant.

I thought it before the B. campestris, but for aught that appears, it agrees with B. Napus, closely allied, i. e. wild rape. Elliot speaks of this as introduced here.


H. D. Thoreau, Journal, August 19, 1860

August 19. See A Book of the Seasons,  by Henry Thoreau, August 19

A Book of the Seasons,  by Henry Thoreau

"A book, each page written in its own season,

out-of-doors, in its own locality.”

~edited, assembled and rewritten by zphx © 2009-2021