In this process, the leaf also receives heat. A leaf’s task is to capture sunlight for photosynthesis, producing food for the tree. The shape gives the tree its best chance of survival based on the environmental factors in the ecosystem. The shape of a tree’s leaves form over the course of a tree species’ evolutionary history. Because these needles last several years on a tree while broadleaves only live for one growing season, trees with needles have an advantage over broadleaf trees, in that the metabolic cost of leaf production can be recovered with photosynthesis over several growing seasons. Trees with needlelike leaves are well suited to sites where water conservation is very important for survival. Needlelike leaves also have a thick coating to prevent excessive water loss. Needlelike leaves have very little surface area therefore, they are not able to capture much sunlight for photosynthesis. Generally, these leaves stay on the tree for more than a year. Trees like pines and spruces have needlelike leaves, and trees like junipers and cedars have scalelike leaves. These have needlelike or scalelike leaves. The other type of tree is an evergreen tree. Mostly, these trees are deciduous and drop their leaves in autumn. These trees have leaves with wide blades exposing a large surface area for photosynthesis ( e.g. These include leaf shape, leaf arrangement, and leaf margins.īroadleaf trees are very common in the United States ( Figure 1). There are many clues to look for on a leaf to help identify the tree from which it came. Leaves are very characteristic of a particular tree species. Examining leaves is one of the most common ways to identify trees.

Leaf guide tree identification