A bit of a stroll
Joanna and I had been to Rickett’s Glen State Park before, its Glens Natural Area boasts no fewer than twenty-two waterfalls and is a National Natural Landmark. When we last visited in April we were disappointed that the very trail we intended to explore was closed due to treacherous conditions. We were determined, so this past Friday afternoon we got hold of a few maps and were off. We found the head of the Falls Trail by a bit after two. Between the steep gorges and sometimes difficult footing (and my incessant desire to stop for pictures) it took us three hours to complete the 3.2 mile loop. We saw eighteen falls ranging in height from 11′ (Cayuga Falls) to 94′ (Ganoga Falls). The image below shows the 13′ Oneida Falls. Information published by the Pennsylvania Department of Conservation and National Resources indicates that hiking along the Falls Trail, comprised of lengths of the Highland Trail, the Glen Leigh Trail, and the Ganoga Glen Trail, is most difficult, that hikers should take extra precaution, wear proper footwear, stay on the trail, and be in good physical condition, but that traveling it is well worth the effort. All of this turned out to be very true indeed.
Perhaps you have noticed that light in the understory of a wood is of quite a different quality than full sun. Indeed, plant biologists have known this for a long time and many have investigated the nature of understory light and its influence on plant growth and reproduction. Scientists have shown that the filtering effects of chlorophyll (the green pigment in leaves) influences the balance between isomeric forms of a light-sensitive growth regulator called phytochrome. Although our eyes cannot distinguish between what is called red light and far-red light, this plant pigment certainly can and these slices of the electromagnetic spectrum cause a reversible change in the phytochrome molecule such that red light stimulates plant growth while far-red light inhibits it. Full sun, above the forest canopy, is largely comprised of red light. The canopy itself filters this light such that only far-red light penetrates into the understory. This is why there is not much growth in the understory and why some seeds and germlings may not develop until a break in the canopy allows red light to reach the ground. In addition to changing the nature of light in the red end of the visible spectrum, the filtering influence of the forest canopy also affects wavelengths of green and yellow such that the light which penetrates the canopy to reach the forest floor below is mostly in the blue end of the spectrum. The analyses below show that wavelengths of green and yellow light are either absorbed or reflected by leaves. The wavelengths which are absorbed drive the transformation of the sun’s radiant energy into chemical energy (as sugar), a process we call photosynthesis, while the wavelengths which are reflected give leaves their green appearance. Thanks to Ross Koning at Eastern Connecticut State University for the data used here.
So once red, yellow, and green have been removed from full sun what remains is mostly blue and explains the heavy blue cast to the original form of the beautiful, and digitally processed, photo above. When I first viewed the image (shown below) I liked it for its composition but didn’t like the blue cast at all. Digital processing allows for this sort of adjustment and in just a minute or two I was able to reduce the saturation and luminance of just the blue tones in the original. While I was at it I didn’t think the white balance accurately reflected the true nature of the scene so I warmed it just one or two hundred degrees. If you compare the before and after versions you can clearly see other, perhaps more subtle differences, but adjustment to blue saturation and luminance and white balance were needed to adjust for the multifarious influences of the luxuriant, and very green, canopy above.