PRAIRIE PLANTS OF SOUTHEASTERN WASHINGTON 



247 



which is seldom over 0.5 inch in diameter, may be abundantly 

 branched all the way to the tip with short laterals (about 3 

 inches long), but more frequently it throws off several laterals 

 at various depths. These vary in direction of growth from nearly 

 horizontal to hearty vertically downward. All are profusely 

 branched to the third or fourth order, especially near the tip. 



Fig. 9. Astragalus (Phaca) arrectus. This root reached a depth of 60 inches. 



The nodules are much larger than those on Lupinus ornatus, 

 often 10-15 mm. in diameter. As in the preceding plant, the 

 legume taste is characteristic. Fourteen plants were excavated 

 on a northeast slope. The deepest reached only 5 feet and 5 

 inches. The average root depth was 4 feet and 9.6 inches. 



