Blinded to the Light
Sometimes, we’re blinded to the light, revved up by the cold, a color spotter in the night.
Paraphrasing Bruce Springsteen’s lyrics, we are often more influenced by popular belief than scientific fact.
In color spotter Robert Kermen’s case, he was blinded to the light, not knowing that it had a greater influence on fall color change than temperature.
He wrote when submitting this report, “I used to think that a leaf’s turning color was triggered by temperature or colder air flow, but when I saw this tree I knew that was only part of it. Just like fruit trees, the side that gets the most sunlight, has the riper fruit. Except that in the case of leaf coloring, the side that gets the most sunlight in the fall turns color first.”
The revelation happened when he saw this unusual tree and confirmed his “aha moment,” when he read Brent Cook’s article, How A Tree Grows.
Cook states, “If you’ve ever seen a tree that has green leaves on one side and red, orange, or yellow leaves on the other, it was probably a result of different amounts of sunlight. In the northern hemisphere, leaves that are on the southwest side of a tree will receive much more sunlight than leaves on the opposite side. Leaves near the top of a tree will also receive more sunlight than leaves at the bottom of the canopy. Consequently, phytochrome (photoreceptors) will trigger abscission (fall color) sooner in leaves getting more sunlight.”
Note that in the above photograph, the shaded side of the tree (left) is still green, whereas the side in the sunlight (right) has turned color. It’s counterintuitive, but a fact of nature. Why that is true, is not entirely clear to me.
Could it be that the sunlit side of the tree senses the change in autumn light waves sooner than that in the shade? We’ll let a dendrologist answer that.
In the meantime, the below photograph answers the question. Jeff Luke Titcomb took it from behind the fence to reveal: it isn’t one tree with two sides, it’s two trees whose canopies have merged.
It is a mystery solved to everyone’s embarrassment. Though, because of Bob’s inquisitiveness, we learned something new about the possibilities that a tree could have two fall color sides, because of light.
Aspen, Beckwourth Pass (10/12/19) Robert Kermen 
M Fork Feather River (10/12/19) Robert Kermen 
Bigleaf maple, Cresta Powerhouse, CA-70 (10/12/19) Robert Kermen
Bob was returning to the Northern Sacramento Valley by way of the Beckwourth Pass (5,221′) (named after legendary mountain man James Beckwourth; his is an extraordinary story) and CA-70 along the Feather River. Color is near peak throughout most of the route.
- Feather River, CA-70 – Near Peak (50-75%) GO NOW!
