Pile the bodies high at Austerlitz and Waterloo. Shovel them under and let me work— I am the grass; I cover all.
And pile them high at Gettysburg And pile them high at Ypres and Verdun. Shovel them under and let me work. (1-6)
When the poem begins, the grass is demanding and assertive. Direct statements and commands such as "pile the bodies high" and "I am the grass" assert nature's sheer power. We see, too, that nature has no feelings. It is just a force that works.
Two years, ten years, and passengers ask the conductor: What place is this? Where are we now? (7-9)
In these lines, we see the effect of nature's pure drive. Nature has been effective in obscuring the vestiges of war from the landscape. People don't even realize when they're passing by famous, deathly battlefields. The grass has erased the signs of human history.
I am the grass. Let me work. (10-11)
In these final lines, nature once again asserts its power. Nature's job is to work, not to remember. And Sandburg seems to be suggesting that this is where we humans come in. It's up to us to remember, and learn from, the traumas of war.