• Wind Cave National Park - Two Worlds

    Wind Cave

    National Park South Dakota

Wildflowers - Russian Thistle

Russian Thistle - Salsola iberica
Russian Thistle - Salsola iberica
NPS Photo by Jim Pisarowicz
 
Russian Thistle seeds are spread as the mature planets break off at ground level. The wind then blows the plant around as a tumbleweed, spreading the Russian Thistle's seeds. Russian Thistle was introduced in the late 1800s from Russia.

Did You Know?

Natural Entrance of Wind Cave

Winds caused by changes in barometric pressure are what give Wind Cave its name. These winds have been measured at the cave's walk-in entrance at over 70 mph. The winds at the natural entrance of the cave attracted the attention of Native Americans and early settlers.