ON OPUNTIA SANTA-RITA, A SPECIES OF CACTUS OF 

 ORNAMENTAL VALUE 



By J. N. ROSE 

 Associate Curator, Division of Plants, U. S. National Museum 



For several years there has been growing in the New York Botani- 

 cal Garden a strange Opuntia which somewhat suggests O. macro- 

 centra, but which is more highly colored and more weakly armed, 

 or not infrequently entirely unarmed. Upon my visit to Tucson, 

 Arizona, in 1908, I found plants of this species in cultivation at the 

 Desert Laboratory of the Carnegie Institution of Washington, and 

 growing spontaneously in waste places in the town itself and in the 

 mountain ranges to the southeast of Tucson. An illustration of this 

 new species recently appeared in the Plant World (vol. xi, p. 224, 

 fig. 6) in connection with which Dr. D. T. MacDougal speaks of 

 this cactus as follows : "The highly colored reddish joints and the 

 delicately tinged flowers make this a very attractive plant, and it may 

 be found in some of the gardens at Tucson," It is, indeed, one of 

 the most attractive of all the Opuntias, and is to be especially recom- 

 mended for planting in the Southwest. If planted in mass, where 

 it could occasionally be irrigated, I know of no other cactus which 

 would be so striking or effective. 



It is to be regretted that persons in charge of public parks and 

 large private or university grounds in that part of the country have 

 not taken advantage of the various Opuntias to obtain unique and 

 pleasing landscape effects. An attempt to show what can be done 

 in this line is to be seen at Mesilla Park, New Mexico, where Prof. 

 E. O. Wooton has very effective groups of these plants. 



The description of the species is as follows : 



OPUNTIA SANTA-RITA (Griffiths and Hare) Rose 



Opuntia chlorotica santa-rita Griffiths and Hare, Bull. N. Mex. Coll. Agr. 

 60 : 64, 1906. 



Plate XV 



Plant 60 to 140 cm. high, nearly as broad as high, with a short 

 and somewhat definite trunk; joints orbicular or broader than long, 

 blue-green, with the space about the areoles and the margins deep 

 purple, or sometimes, especially when young, pinkish or purplish 



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