Tree Leaves Article - Connor Chatwell

Many trees’ leaves change color and shed in the fall. There are many varying factors as to why this happens. These factors include soil, weather, and species of tree.

In the summer and winter, tree leaves are green due to chlorophyll. They are green all spring and summer then, when they go dormant for the winter they change color. Leaves stop going through photosynthesis in the fall to prepare for winter, this causes the leaves to change color as the chlorophyll begins to break down. The green color starts to disappear so reds and oranges become visible. The red and orange pigments are known as carotenoids. Anthocyanins also cause colors such as red, pink, and purple. Trees that lose their leaves are known as deciduous trees. Trees that do not lose their leaves are known as evergreens.

Weather can affect the colors of the leaves. The colder it is,the redder the leaves will be, but if it gets too cold too soon the reds will show weaker. Lots of rain and overcast will increase the intensity of the colors. In simpler words, as long as it's miserable outside, but not miserable too soon, the trees will look beautiful. Nutrients in the soil can also affect the color. Low amounts of nitrogen and other nutrients will result in more reds in the leaves. The reason this is is because more anthocyanins will be produced in order to preserve nutrients left in the leaves to supplement for the lack of nutrients in the soil.

On the stem of a leaf, a layer of cells gradually builds up to severing the leaf from the tree. The layer of cells is known as the abscission layer, when this layer builds us it closes the wound from the severing to prevent any injuries that could come from the leaf being severed.If the leaves were not severed major breakage can happen to the tree. Because there are no leaves come spring time, it is easier for trees to pollinate as leaves are not in the way of the pollen when it is blown by the wind.

Maple trees can lose their leaves as early as June or July. When this happens it can be caused by many things. These include droughts, sudden changes in temperatures, or various insects invading the tree. The leaves will usually turn yellow or brown and 25 to 30 percent of leaves will fall.

Oak trees can be both evergreen and deciduous. Deciduous oaks shed their leaves in late fall whereas evergreen trees will shed old and unhealthy leaves in the fall or early spring in time for new leaves to bud.

Larches, which are a type of pine tree, turn bright yellow and gold in the fall. In the spring they are some of the first trees to bud.

Deciduous trees lose their leaves and change color in the fall. The soil, weather, and species of a tree can affect when leaves change color and when they shed.

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