The overview features color images that the fall foliage of 47 tree and shrub species.

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The Splendor that Autumn

Every fall we revel in the beauty of the autumn colors. The mixture of red, purple, orange and yellow is the an outcome of chemical processes that take location in the tree together the seasons readjust from summer to winter.

During the spring and also summer the leaves have actually served together factories where many of the foods essential for the tree"s expansion are manufactured. This food-making procedure takes location in the leaf in many cells include chlorophyll, which offers the sheet its eco-friendly color. This extraordinary chemistry absorbs from sunshine the power that is offered in transforming carbon dioxide and also water to carbohydrates, such together sugars and starch.

Along v the green pigment space yellow come orange pigments, carotenes and xanthophyll colours which, for example, offer the orange shade to a carrot. Most of the year these colors space masked by good amounts of eco-friendly coloring.

Chlorophyll division Down

But in the fall, since of alters in the size of daylight and changes in temperature, the leaves protect against their food-making process. The chlorophyll breaks down, the green color disappears, and also the yellow come orange colors come to be visible and also give the leaves component of their loss splendor.

At the very same time other chemical alters may occur, which form additional colors through the development of red anthocyanin pigments. Some mixtures provide rise to the reddish and also purplish autumn colors of trees such together dogwoods and also sumacs, if others provide the sugar maple its brilliant orange.

The fall foliage of part trees present only yellow colors. Others, like numerous oaks, display screen mostly browns. Every these color are due to the mix of varying quantities of the chlorophyll residue and also other colors in the leaf throughout the fall season.

Other changes Take Place

As the fall colors appear, other changes are acquisition place. In ~ the point where the stem of the sheet is attached come the tree, a special layer of cells develops and gradually severs the tissues that assistance the leaf. In ~ the same time, the tree seals the cut, so that when the leaf is finally blown off by the wind or falls from its very own weight, it pipeline behind a sheet scar.

Most that the broad-leaved tree in the North shed their pipeline in the fall. However, the dead brown pipeline of the oaks and also a few other types may remain on the tree until growth starts again in the spring. In the South, where the winters are mild, some of the broad-leaved trees room evergreen; the is, the leaves stay on the trees throughout winter and keep their green color.

Only part Trees shed Leaves

Most that the conifers - pines, spruces, firs, hemlocks, cedars, etc. - are evergreen in both the North and also South. The needle- or scale-like pipeline remain green or greenish the year round, and also individual leaves might stay ~ above for 2 to four or an ext years.

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Weather Affects color Intensity

Temperature, light, and water supply have an influence on the degree and also the term of loss color. Short temperatures above freezing will certainly favor anthocyanin formation creating bright reds in maples. However, early on frost will weaken the brilliant red color. Rainy and/or overcast days often tend to increase the soot of fall colors. The finest time to gain the autumn shade would it is in on a clear, dry, and cool (not freezing) day.