In my close reading of "Reapers", I seen two stories in one. The first half of the poem, which refers to slaves as "Black reapers" depicts slaves working the fields. The second half of the poem depicts "Black Horses", which I believe signifies a movement towards industrial agriculture.
Each individual story begins with the word "Black". In the first half of the poem we are introduced to slaves that are sharpening their scythes themselves, as that is the acceptable thing to do. After they finish sharpening them, they "place the hones/ In their hip-pockets as a thing that's done". This is just an acceptable act, in which they will carry their hones around while performing manual labor. The word that stood out to me in this first half of the poem that would contrast the second portion of the poem, is "start their silent swinging". This notion of silence and peace in manual labor is differs from the second portion of the poem.
The second portion of the poem, which I believe is a metaphor for industrial agriculture is less peaceful. Black horses have replaced black reapers. "A field rat, startled, squealing bleeds." This sentence alone breaks the silence of the reaping. It depicts industrial agriculture as having disregard for life or whoever it walks on. The main goal of industrial agriculture was to increase the production of the product, sometimes with disregard to morals or ethics. Overall I believe that the structure of the poem is very important, and although grouped together in 8 lines, "Reapers" provides readers with two different methods of agriculture.