I'm uncertain about the meaning of shade in the last line of Jean Toomer's "Reapers"
Black reapers with the sound of steel on stones Are sharpening scythes. I see them place the hones In their hip-pockets as a thing that’s done, And start their silent swinging, one by one. Black horses drive a mower through the weeds, And there, a field rat, startled, squealing bleeds. His belly close to ground. I see the blade, Blood-stained, continue cutting weeds and shade.
Is it a noun (the blade is cutting shade) or a verb (the blade shades away at the author watches)?