Opposite Leaf Structure

Look at the tip - the part farthest away from the stem - of several leaves. Choose big leaves that aren’t starting to decay. Observe the angle formed when the two sides of the leaf come together at the tip. Look only within ½ cm of the tip, not farther down the leaf. Acute leaves have angles less than 90 degrees, obtuse leaves form angles greater than 90 degrees. You’ll need to approximate, as every leaf may be slightly different. Just because a leaf is long and thin doesn’t mean the tip is acute. Use a magnifying glass to take a close look at the tip of thin leaves.

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