"Reapers" . . . is written in rhymed quatrains, rhymed so insistently, in fact, that it is possible to read the poem as having only two rhyming sounds for its eight lines. It is also rendered in complete, conventional sentences, and it has a fairly consistent iambic rhythm. The appropriateness of these conventions appears where they are most consistent:
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.
The rhythmic repetitions of the form stand for the repetitive nature of the work, which appears most obviously in the nearly perfect iambic line that represents the resumed swinging of the scythes. This sort of work is repetitive in a physical sense, relying as it does on a few movements reiterated again and again, and in a temporal sense, since it must be done every day, every season, season after season. It is "a thing that's done," a habit.
Toomer does not print the break between stanzas as a physical break, but everything changes there nevertheless:
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.
The break represents a major change in the life of this rural area, the change from manpower to machines, which changes everything else as well. As Toomer put it in a letter to Frank, "The supreme fact of mechanical civilization is that you become part of it, or get sloughed off (under)." The line describing the death of the field rat embodies this change in meaning and in sound. Instead of working slowly and rhythmically, the mower moves on ineluctably, even killing the living things before it, which make a sound that is the very antithesis of the soft silent swinging of the scythes. The dying squeal of the rat affects the poetry itself, which is least iambic and most interrupted just here, as if the line itself were cut mindlessly and inorganically.