What kind of cactus is this?

Question

http://michaelguo.com/images/IMG_4374.jpg

I took a picture of it while I was in Arizona at Goldfield Ghost Town and am wondering what species it is.

Thank you!

Answer 1

It's called a "Cholla" (pronounced choy-ya) probably a Opuntia fulgida (common name: Jumping cactus or Chain Fruit cactus.) These cactus are very common in Arizona (the Sonoran desert), they grow practically everywhere in the low desert areas. They don't really jump but the segments detach very easily when they are brushed against and can become very painfully attached to your skin or clothing.
Another common cholla that looks like this one is a Opuntia imbricata, called Tree Cholla, but they are more common in the Mojave desert as is Opuntia bigelovii, called the Teddy Bear cactus which also looks like this one.
I checked the USDA Plant Database on this plant, just to be sure, and it is not the Bergocactus. While it looks somewhat like a cholla it is a native of the Mohave desert (mainly California) and not like the plant you are asking about in other respects.

Answer 2

Bergerocactus !

The golden cereus (Bergerocactus emoryi) is a species of cactus. It is the sole member of the genus Bergerocactus, named after Alwin Berger. The plant is also known as golden spine cereus or snake cactus, though this latter name also applies for Echinocereus pensilis.

This cactus is frail, appear in clusters, has up to 20 ribs and ramifications. It is rarely higher than 1 m, and diameter is usually less than 5 cm. Flowers are yellow and appear near the plant's apex, reaching 2 cm in length and diameter. They are tunnel-shaped.

Answer 3

Ellen is correct, it is a Cholla. The spines contain poison. Be glad you didn't stumble into it. Had a friend who did, what a mess.