Some people believe that ‘God’s Country’ is an area of Northern California, especially that area where Sequoia sempervirons and Sequoia giganteous trees still are or were located. These trees are the Redwoods and some scientists think they evolved from a common species, including myself. Some people believe ‘God’s Country’ is all of the United States of America. I do not think there is a ‘God’, a ‘Satan’, a ‘Heaven’ or a ‘Hell’, except what people fashion here.
Well, so I ask, Why is Sequoia sempervirons tall and why is Sequoia giganteous large? This question I posed at first to myself in a journal I kept when I attended Pacific Marine Station, in ‘God’s Country’. You see, if you believe in an all knowing, all powerful and omnipresent ‘God’, then that question is answered. ‘God’ made them that way.
For Sequoia sempervirons being tall I wrote in the journal there must be a ground to sky gradient up which they climbed and I thought and I wrote continuing the journal. I said some stuff about insects being co-dominant with humankind and diverse. I questioned, Why are insects so diverse? I came up with a possible answer that they fly by comparison with other taxa of Arthropoda and listed a number of advantages the ability to fly gave insects. Flying as presented by many different species of insects is a ground to sky gradient but is it alone the only gradient Sequoia sempervirons climbed?
Today, as I said earlier in this blog, Redwood Trees depend on fire to maintain their community, to germinate their seeds and clear choking brush. The fires of Redwood Forests do not usually burn down the trees. The Redwood Trees are very resistant to fire and they have some help where they are found today in California. Sequoia sempervirons is the Coast Redwood, and on the coast where those trees grow fog forms at night and in the morning begins to rise in the warming sunlight as a ground to sky gradient. When the fog reaches the height of the needles, lower in young trees and higher in taller trees, the fog condenses on the needles and drips to the ground. These are the trees that early settlers told stories of “that the trees reached the clouds”. Actually the Coast Redwood poke through the clouds on the coast and the further they do so the more sunlight they can get for photosynthesis to produce seeds and to maintain themselves.
The Coast Redwood is in a race against time and other Redwood Trees to climb into and above the fog so to get the most sunlight they can. The rising of the fog is another ground to sky gradient which pushed Redwood Trees taller.
The more I thought about it and did the observations the more ground to sky gradients that would affect the height of trees I came up with.
I have not said yet what I think is responsible for Sequoia giganteous separating out as a separate species from the ancestral species under the genus Sequoia. The difference it exhibits apart from Sequoia sempervirons is that it is morphologically more robust (larger, bulkier). When earthquakes occurred in California some trees were uprooted and crashed to the ground knocking branches off of surrounding trees. This is natural selection. The trees that were left behind standing in relatively good shape had stood their ground and were around to spread their seeds which contained the genes that would express a hardier morphology.
Now both Sequoia sempervirons and Sequoia giganteous are tall species, and both are fairly large. They are subject to nearly the same conditions of earthquakes, insects, fog and fire in some places. I think that if you could observe over the courses of several generations of the trees you would find differences that continue to separate the species.
For those who do not know what a ground to sky gradient is, it is a characteristic that varies as one measures it as a function of height above ground. Please think of a valley to the top of a hill/mountain. It is an obvious gradient one could climb. Now the first ground to sky gradient I mentioned above is insects in flight. Different species of insects are able to fly to different heights without a rest, say on a tree branch. The higher they can get, if they affect the tree, the greater the affect they can have on the tree, bottom to top. The second ground to sky gradient I mentioned above is the rising of the fog. As the fog rises it wets more of the tree and at the same time dims the amount of light affecting the needles/leaves of the tree. To reach the greatest levels of photosynthesis it can the tree needs to have its needles/leaves out of the fog. However to wet the ground below, so fire does not have such a bad effect on the tree it is good to have some needles/leaves drenched in fog. How the branches stick out from the tree is a gradient.