30 



BULLETIN 465, U. S. DEPARTMENT OF AGRICULTURE. 



Well-developed tubers of the cultivated variety average about 

 three-fourths of an inch in length by three-eighths of an inch in 

 diameter when dried. Tubers from wild plants are usually much 

 smaller and have a greater proportion of fiber. The general appear- 

 ance of chufas and of tubers from a wild sedge is well shown in 

 figure 28. 



Chufas are known also by the vernacular names earth almonds 

 and ground nuts, and the plant as nut grass and cache-cache. 



Fig. 28. — Tubers- of wild and cultivated chufas. (Natural size.) 

 DISTRIBUTION. 



The northern boundary of the natural range of the chuf a is marked 

 by the following localities: Southern New Brunswick, southern 

 Ontario, northern Nebraska, New Mexico, Arizona, and the Columbia 

 River valley. The plant seems to be absent from most of the Great 

 Basin and Rocky Mountain regions. From its northern limit the 

 plant ranges southward over the remainder of the continent. (See 



