26 



BULLETIN 465, U. S. DEPARTMENT OF AGRICULTURE. 



but they attain a much larger size. The largest specimen exam- 

 ined by the writer was 2 inches in its longest diameter and 1 inch 

 thick. Including the bud and a short stalk at the base, the entire 

 tuber may measure as much as 5 inches in length. The mature 

 tubers of plants from the Northwest are more or less flattened, the 

 shape being comparable to that of the ordinary edible crab. The 

 smaller tubers are more nearly spherical (varying to ovoid), and this 

 is the shape of even the largest tubers of eastern plants that the 

 writer has seen. The sheaths of the tuber, being of a darker color 

 than the body, are conspicuous. 



DISTRIBUTION. 



Sagittaria latifolia is found from the Atlantic coast to the Pacific, 

 its range covering practically the whole United States (fig. 26). 

 Areas from which it apparently has not been reported are peninsular 

 Florida, the southern two-thirds of Louisiana and Texas, New Mexico, 

 Arizona, and southern California. The northern limit of its range is 

 marked by the following localities : Vancouver Island, Saskatchewan 



Fig. 24. — Various shapes of wapato leaves. (About one-tenth natural size.) 



River, and southern Ontario and Quebec. Sagittaria arifolia is con- 

 fined to States from Michigan and Kansas westward. Its range is 

 largely included in that of S. latifolia, although it has been collected 

 in New Mexico. The two species are distinguishable with certainty 

 only upon the basis of mature seeds, and for all practical purposes 

 may be considered as one. 



PROPAGATION. 



The wapato may be transplanted by means of both seeds and tubers, 1 

 but the latter are the most reliable and give the quickest results. 

 They may be set with the bud just beneath the surface in mud bottom 

 under a foot of water or preferably less. The plants will grow in 



1 It is probable that tubers of Sagittaria chinaixis. which are in market wherever there 

 is a large Chinese colony, and which are also on sale by seedsmen, may be substituted 

 for those of wapato with satisfactory results. 



