I was talking with my team of fellow data collectors at Trees Atlanta about how doing that project changed the way we look at trees. We all agreed that it made us evaluate trees much more closely everywhere we went.
In our data collection for Trees Atlanta, we measured trees that had been planted within the last five years. We checked their trunk size in a couple of places and we looked to see if their leaves had chlorosis (were turning yellow). We also looked to see how much of the crown (the leafy part of the tree) had dieback (no leaves).