Opuntia subulata monstrose
(This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots).
This is a monstrose form of the Opuntia subulata, also known as Austrocylindropuntia subulata.
Origin and habitat: Probably native only to the Andes of Peru
Description: It is a popular well-known shrubby cactus with several main branches from the base or a small tree with a simple erect trunk and a large almost hemispherical top often 3 to 4(-5) meters high. The leaves are relatively large and persistent.
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz