The Pipestone National Monument's Sioux quartzite prairie supports two species of cacti. The rocky outcrops and shallow soil along the cliffline areas provide the Plains Prickly Pear Cactus (Opuntia macrorhiza) with a niche with little competition for resources. The Prickly Pear cactus blooms for a short time in early July, displaying beautiful and fragile looking yellow flowers.  


Family
 Common Name      Scientific Name 

Cactaceae
Prickly Pear	Opuntia macrorhiza
Brittle Prickly Pear	Opuntia fragilis