The trees are shedding their leaves. It's a good time to explore botanists' methods to identify plants based on their leaves. Leaves can be used to identify the type of plant. The shape, size, color, and texture of the leaves can be used to distinguish different plants. Additionally, the veins and margins of the leaf can provide additional information. Let's take a look at them.

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Venation:
The arrangement of veins in a leaf, vital for nutrient transport. Examples include parallel veins and pinnate veins, spaced along a central midvein, and palmate veins diverging from a point.

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Shape:
Pinnately lobed leaves resemble feathers, obovate leaves are egg-shaped, and palmately lobed leaves spread radially. Linear leaves are narrow, sagittate leaves are arrowhead-shaped, ovate leaves are egg-shaped, and lanceolate leaves are relatively narrow.

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Arrangement:
Leaves may be simple or compound. Simple leaves are undivided, while palmately-compound leaves have leaflets radiating from the petiole. Pinnately-compound leaves have leaflets arranged along a stalk-like extension, and bipinnately-compound leaves have leaflets attached to second-order rachises.

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Margins:
Entire margins are smooth, crenate margins have rounded teeth, dentate margins have square teeth, serrate margins resemble a saw, and lobed margins extend more than 1/4 of the way to the midvein.

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Leaf Arrangement on Stem:
Leaves may be alternate, spirally or planar, opposite, or whorled in groups of three or more at each node. Understanding these features enhances the ability to identify diverse plant species.

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Reference:

• Elmer, N..(2020). Botany Basics: Understanding Leaves. Biodiversity Blog. The University of Texas at Austin Biodiversity Center.