I’ve been working on tree identification for the past two years. While I have a book for the Southeast, the New England area is a different story. Because I haven’t gotten a book yet, I rely on the internet (scary notion) for my information. I noticed a problem in both looking online and trying to identify tree leaves still on the tree vs. fallen tree leaves. Their sizes don’t always match.
This is not specifically a New England issue, just one I noticed since not relying on a book. I had no idea what this problem was, and the frustration of seeing skinny oak leaves with the same names as wide oak leaves increased. I started to wonder if New England tree naming was the same as Boston street naming, have several different trees with the same name, and only the locals will know what’s going on.
Well, one day in my terrestrial ecosystems and the carbon cycle class had a lecture on
photosynthesis. The majority of the information was repeat from elementary school pictures of the little photosynthesis cycle; however, my professor touched upon a fact I had never heard of: the difference between shade and sun leaves.
Even as I write this, the concept seems so simple that I feel silly for not having thought
about it. The idea is that trees can have multiple sizes and even shape of leaves depending on where they are on the tree. The sun leaves are, for example, on the tops of the trees where they gain the most sunlight. They wind up being much skinnier than their lower siblings called the shade leaves, which are fatter to collect any sunlight escaping through the top of the canopy.
So online, whenever I looked for pictures, I looked for actual ones rather than illustrations, and those real ones were of leaves that people found. Meanwhile, I looked back at my book on Southeastern trees and did not even realize that the illustrations often showed two different looking leaves. I took for granted the fact that the authors of the book knew this little fact I had never thought of.
So, Moral of the Story
Two types of leaves exist on a lot of trees, not all, but enough to frustrate you if you’re using google to look up pictures of leaves and the same species comes up with several different looking leaves. Now, do not confuse this a picture of what someone claims to be a sugar maple with seven points vs. another picture of one with three points. The only major differences in the leaves are thickness of the leaf and how wide or narrow the curves are between the points.
I’m honestly not sure how much this post will help people. Hopefully, I am not the only one previously oblivious to this obvious piece of information. With that said, tree identification is a wonderful way to add depth to perception of the natural world around them. You don’t call all your friends Bob or Sue, and you know how different each friend is. The trees, ferns, flowers, birds, etc. are the same and learning at least a little something about them enhances the exploratory experience, even if it’s just learning that not all your friends are fat or skinny! Happy trails, guys.