In other plants, leaves vary between individuals (as sugar maples) or even dramatically within an individual (as red maples), or even within a single leaf (red maples). I found no pleasure in the silent trees, the falling fir-cones, the congealed relics of autumn, russet. To make a countryman understand what feuille-morte colour signifies, it may suffice to tell him, it is. In some plants the color production is quite uniform, as in hobblebush or blueberry. Amber, Auburn, Crimson and Other Colorful Words for Autumn Foliage Feuille morte. Anthocyanins and carotenoids produce orange hues. Leaves change color during the autumn because the amounts of pigments change as the leaves prepare to fall from the trees. Anthocyanin and chlorophyll produce brownish colors. In these leaves, the actual shades of red are the consequences of the amounts of anthocyanin, the retention of carotenoids (or even a little chlorophyll). This is the most common color of autumn leaves about 70 % of shrubs and trees at the Harvard Forest produce anthocyanins during the senescence of the leaves. Most interesting are leaves that turn red, because this color is the result of the active synthesis of anthocyanin pigments just before the leaves fall from the trees. Such leaves are a pale green in color, or perhaps yellow-green from the mixture of chlorophyll and carotenoids. In unusual cases, sometimes in winterberry holly, a fair amount of chlorophyll is left in the leaves when they fall. In fact, in some ways a wet summer would be detrimental to fall leaves heavy rain or wind could knock leaves off before they have a chance to turn. Carotenoid pigments are also lost from the plastids during aging, but some of them are retained in the plastids after the chlorophyll is removed this produces autumn leaves with yellow colors. Under optimal conditions this process of chlorophyll loss is very orderly and allows the plants to resorb much of the nitrogen in the structure of the pigment molecule. All leaves gradually lose chlorophyll during the growing season, and this loss accelerates before leaf fall. Leaves change color during the autumn because the amounts of pigments change as the leaves prepare to fall from the trees.
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