My son and I recently drove past this 'tree claim' out in the middle of the prairie near Ogallala, Nebraska. It is a great example of how policy (plant trees to get your land claim) affected landscapes in Nebraska. Of course, there is no homestead now. Just a bunch of lonely cottonwoods, planted in rows.
Tree claims , as part of the Timber Culture Act of 1873 (the original Homestead Act was in 1862) were mentioned in Laura Ingalls Wilder's By the Shores of Silver Lake:
“This country’s going to be covered with trees,” Pa said. “Don’t forget that Uncle Sam’s tending to that. There’s a tree claim on every section, and settlers have got to plant ten acres of trees on every tree claim. In four or five years, you’ll see trees every way you look.”