CACTUS LANDSCAPES. 



THE SINGULAR CACTUS FLORA OF OUR GREAT SOUTHWEST. 



HERE are 140 species of 

 the cactus family in th* 

 United States, all of 

 which are embraced in 

 five genera, or practical- 

 ly in four genera, as the 

 fifth contains only one 

 species. The four prin- 

 cipal genera are as fol" 

 lows : cereus, 34 species; 

 echinocactus, 23 species; 

 mamillaria, 30 species ; 

 opuntia, 52 species. It is 

 difficult to describe the differences between these 

 genera in popular language. There are but two 

 or three species growing east of the Mississippi 

 friver. About half a dozen species are spread 

 over the Great Plains between 

 the Missouri river and the 

 Rocky Mountains, a few of 

 them reaching into Montana 

 and Idaho. In Utah and 

 Nevada many additional 

 species occur, mostly species 

 which are also common farther 

 south. But in the desert re- 

 gion of the southwest, extend- 

 ing from western Texas, 

 through New Mexico, Arizona 

 and southern California, the 

 species become very numerous, 

 and form a characteristic fea- 

 ture of the vegetation. The 

 distribution of the species is 

 by no means uniform, how- 

 ever. Some species are spread 

 over nearly the whole field, 

 while others are more or less re- 

 stricted. We can here only take 



notice of such species as would either on account 

 of their abundant and constant appearance, or from 

 their peculiar and striking characters, attract the 

 attention of the traveler. 



The species of the genus mamillaria are mostly small 

 roundish pulpy bodies, seldom more than three or four 

 inches in height or diameter, studded with tubercles 

 which are densely covered with spines. Most of the 

 species of the genus echinocactus are also low, ovate 



or cylindrical-ovate bodies, marked by more or less prom- 

 inent ribs running from base to apex, on which are 

 situated the tubercles and spines. The same general 

 statement will apply to many of the species of the 

 genus cereus, especially of those inhabiting New Mexico 

 and Texas. In Arizona and southern California some 

 of this genus have tall, columnar trunks. 



The genus opuntia, commonly known as prickly pear, 

 has some species with flattened, and some with cylin- 

 drical, branching joints. Some of the species are low 

 or spreading on the ground, and others assume a branch- 

 ing or bushy form. 



A favorite region for cactus plants is in western and 

 southern Texas ; especially do they abound on the bills 

 and bluffs of the Rio Grande river, extending up the 

 country of the Pecos into New Mexico and over the 

 region formerly known as the Staked Plains. 



In southern and southwestern Texas, in the countries 



Fig. P. A Plant of Opuntia Whipplei. 



bordering the Rio Grande, several species of the flat- 

 jointed opuntias, particularly Opuntia Engelmanni and 

 Opuntia Lindheimeri , occur. These grow from four to 

 six feet high, extending over large tracts of country and 

 sometimes forming thickets which it is difficult to pass 

 through. 



Within a few years the cattle raisers of this region 

 have found means of utilizing these plants for the feed- 

 ing of cattle, Ordinarally, cattle do not touch these 



