Flora for Hikers: Cacti

The Cactus Family is well represented in Arizona.  In fact, there are more species of cacti in Arizona than any other state except Texas   What makes a cactus a cactus?  Flowers and fruits, of course but it's those nasty spines that grab our attention and often an accurate identification is possible without flowers or fruits being on the plant in question.  Many of these plants are useful for all sorts of reasons, even being edible.  Ever play catch with a clump of cholla?  Me either, but we'll find out how these plants were used to inflict suffering during war time, so heads up. Samples/specimens provided.