It must be a sight: A guy in his 70s walking around a campus of young people, holding an 11-x 17-inch campus tree atlas, walking up to trees, feeling their leaves and trunks.

Once I have a quadrant on my tree map oriented, I try to keep my finger near my present location. I try to cover the entire quadrant, looking at each tree, whether I recognize it or not. Trees that are new to me get special attention. Rather than take a picture, I have been trying to create a memory image of that tree. The idea is that in future walks, I will stop at those trees I do not recognize immediately and try to remember them all over again.

In about six hours, I have walked six quadrants. That means it should take me another 19 hours to walk the remaining 19 quadrants. And that’s just for starters, because I expect to walk the campus again, looking to see if I can recognize all the trees.

Why can’t I be this organized with other things in my life? I could use a quadrant system to clean or to organize my room – or the garage – or the backyard. I could check off each quadrant as I finished working on it. I could make comments in the quadrant about things I still needed to do.

Do you remember the game Battleship? You drew a big square on a paper, and divided it up into, say, 25 quadrants (A1, A2, A3). Then, you entered an abbreviation for types of ships (A = aircraft carrier, B = battleship) in each of several squares. Your opponent would say “B4,” and you would look in that square to see if he had “hit” one of your ships. If he did, that ship would be crossed off and it would be your turn to attack his fleet.

It seems I am enjoying both worlds with my campus outings. I am learning the trees and, at the same time, I am playing a game of Battleship. But instead of crossing out sinking ships, I am crossing out identified trees.

Unlike so many of my hobbies, this hobby allows me to get outside – to breathe lots of fresh air and walk for hours. Now I ought to find other hobbies with outdoor quadrants — like walking the neighborhood blocks (quadrants) where I live.

Mr. Ebsen may be contacted at Robertebsen@hotmail.com