I bequeath myself to the dirt to grow from the grass I love,
If you want me again look for me under your boot-soles.

You will hardly know who I am or what I mean,
But I shall be good health to you nevertheless,
And filter and fibre your blood. 

Failing to fetch me at first keep encouraged,
Missing me one place search another,
I stop somewhere waiting for you. 

     – Walt Whitman, from "Song of Myself"