What causes leaves to fall in autumn?

Green house control group: Tree 1 is placed in a green house and exposed to average heat and light, similar to average autumn whether Experimental Group: Tree 2: Will have 80 temp. and 14 hrs. of light. read more

Sunlight and the cool nights of autumn cause the leaves turn this glucose into a red color. The brown color of trees like oaks is made from wastes left in the leaves. It is the combination of all these things that make the beautiful fall foliage colors we enjoy each year. Plants are busy growing all summer long. read more

Sun-lit autumn days stimulate leaves to produce sugars, and chill nights close the veins leading into and out of the leaf, locking in the sugars—which in turn lead to the production of anthocyanins and their crimsons and violets. read more