Why are Summer Greens Boring?

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Research suggests that Healthcare art should show lots of "verdant vegetation"; in other words there should be a lot of green.

But the greenest time of year (mid-summer) is not when I want to be taking pictures. I find the continuous wall of dark green to be boring. There is just not enough variation. Fall has a rich mix of yellows, golds and reds; but Fall can have negative connotations - the impending end of the growing season; death. Not appropriate for healthcare.

Spring foliage is better than Fall. The leaves are fresh and there is a lot of variation in color and texture. But that magical time, when all the leaves emerge is over in a few weeks.

Reflecting on the variations in green in nature made me wonder: why is the green foliage in summer so monotonous?

I approached an expert, Dr. George Yatskievych, a botanist at the Missouri Botanical Garden.

Can you explain why summer greens are so boring? Is it related to the relative proportion of the different kinds of chlorophyl's or other chemicals in the leaves? Why does it vary with the season? 

I don't know why the summer greens seem boring.  I prefer to think of them more as subtle.  After all, eastern red cedars and shortleaf pines are still dark green and sycamores still tend to be a lighter green than oaks.  I think that you have to look harder for the variation, but it is there.

Plants produce only two kinds of chlorophylls, known as chlorophyll a and chlorophyll b.  Each of these has a unique, slightly different wavelength of light reflectance, but they do not contribute much to color variation in the green leaf.  In the spring, as the leaf develops, there is a lot of new chlorophyll produced in the rapidly dividing cells, but after the leaf has matured the amount produced is much less, tapering off.

Most often, the strong green color that results from the production of chlorophylls masks a variety of secondary compounds of various color, such as the reds and purples of anthocyanins and the yellows and oranges of carotenoids.  These occur in much greater variety than chlorophylls and are (along with some other chemical groups)  the compounds responsible for fall color.  To some extend, these compounds can modify the green of the leaf, darkening or lightening it somewhat in spite of the masking chlorophylls.

Leaf color is determined by more than just chemical compounds. In some species, the chloroplasts in the leaves physically align themselves so as to absorb the maximum amount of light.  In other leaves, the chloroplasts do not do so, or at any rate do so less efficiently.  This pattern of chloroplast orientation can affect light reflectance and thus the appearance of the leaf.  In other species, leaves are covered with waxy, powdery, or hairy indument, which can make them appear lighter or darker.

Comments

[Elaine Poggi]

Henry, the problem you are having with boring summer greens is that you are photographing in the wrong place... Pack your camera (and tripod) and hop on a plane to Tuscany! The greens here are so varied - the olive trees are a silvery green; the cypress trees are much darker; the fields of wheat contrast with the these greens. Throw in a 15th century stone villa, colorful flowers here and there, a few sheep grazing, a blue sky with white cotton-like clouds, and you have a very stunning photo!!