148 THE FANTASTIC CLAN 



ing and grow both outdoors and in; but with zero weather 

 they require protection. 



ThoRNBER'S ChollA (Opuntia Thornberi) 



(Named In honor of Professor J. J. Thornber, botanist of 



the University of Arizona and one of the authors 



of this book) 



How to identify and how it grows 



Thornber's Cholla is a shrub growing from two to four 

 feet tall, with fantastic branches irregularly whorled and 

 long angular joints six to twenty-four inches in length and 

 yellowish green. It appears waxy, is densely covered with 

 long tubercles or knobs, and has short light-colored spicules. 

 The spines are three to twelve, one-quarter inch or less in 

 length, and very sharp. They are covered with thin straw- 

 colored or brownish yellow sheaths. The flowers of this 

 Cholla are of yellowish and red shadings, appearing mostly 

 at the tips of the branches. The fruit is quite dry when ma- 

 tured and Is distinctly tubercled. 



How to grow 



Young plants may be set out at any season, also cuttings in 

 spring; they thrive best in rocky or gravelly soil, watered 

 once a month until the plants are established. They grow 

 outdoors or Indoors and are not injured by twenty-five de- 

 grees of freezing; but at zero they need protection. 



Spiny Tree Cholla; Tasajo (Opuntia spinosior) 



(The name spinosior means "more spiny," referring to the 

 many spines of the joints of this species) 



How to identify and how it grows 



The Spiny Tree Cholla grows to a height of fifteen feet 

 and has a woody trunk several feet long with ascending 



