Other Images - William H Wiley

Nature and Wildlife Images in the Wild

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William H. Wiley



1221 Rockhurst Dr.

Lincoln, NE 68510

Autumn Thistle in Yellowstone National Park

Thistle is the common name of a group of flowering plants characterized by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles occur all over the plant – on the stem and flat parts of leaves. They are an adaptation that protects the plant from being eaten by herbivores. Thistles attract goldfinches and thistle-seed feeders and are an important nectar source for pollinators. Bumblebees benefit from thistles for their high nectar production while the monarch butterfly relies on taller large-flowered thistle species for its migration.