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Planet Earth

What Is This? A Bouquet of Glass Flowers?

Hint: Its tannin content can poison horses, and the flower-like things are actually hairy appendages.

By Andrew GrantApril 28, 2010 5:00 AM


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Dr Havi Sarfaty, Veterinary Association, Photo Courtesy of Nikon Small World | NULL

Dr. Uma Ganesan/Olympus Bioscapes Digital Imaging Competition

ANSWER: An oak leafThe Northern Hemisphere is home to about 450 species of oak. This micrograph image of an oak leaf¹s surface reveals bunches of tiny hairs called trichomes, which concentrate light for photosynthesis and reduce water loss. Oak leaves also contain tannins, which can poison horses that have a taste for foliage.

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