Here's a mowing thought to those reading this. If you mow so close that your tractor tire brushes the edge of the trees, the impact will "prune" the tree and not allow growth to continue where the tire contacts the tree. This didn't seem to be a big issue when we lived in Maine where it was wet and cool but it sure is here in dry and warm Ohio. If anyone wants I can post photos.
A further thought to windbreaks is to plant a row of (northern white) cedars/Aborvitaes in addion to the windbreak. They grow really fast, espcially with fertilizer and add to the windbreak by the variation in height. I plant those on a four foot center and have photos of this as well.
The addition of windbreaks and trees has been the greatest addition to our land that I have done. They take time to grow but water, fertilizer and pruning speeds up the process and before you know it you have something to admire.