PRAIRIE PLANTS OF SOUTHEASTERN WASHINGTON 



240 



graphed, together with a meter stick, for purposes of comparing 

 lengths. It was usually necessary to double the root one or more 

 times in order to get it all on the ground glass at a distance close 

 enough to' show the details of structure. Root-systems of the 

 following plants were studied. 



<F7\ 



Fig. 7. A root of Lupinus ornatus 

 with a length of 163 inches. 



Fig. 8. Lupinus leucophyllus has a much 

 larger transpiring surface and a smaller ab- 

 sorbing surface than the preceding species. 

 Note the large root tubercles. 



Lupinus ornatus (Fig. 7) 



Only two species of lupines occur widely distributed on the 

 high prairies of eastern Washington. Of these Lupinus ornatus 

 is the more xerophytic, while Lupinus leucophyllus rarely occurs 



