PRAIRIE PLANTS OF SOUTHEASTERN WASHINGTON 281 



meters in diameter. These are poorly branched, not often 

 giving off roots of the fourth order. The tip of the main root 

 likewise is little branched. The roots are black externally, 

 grayish inside, have a characteristic odor, and dry out and 

 shrink rapidly upon removal from the soil. Eighteen plants on 

 a northeast slope were examined. They had an average root 

 depth of 5 feet and 0.4 inch. 



Heuchera glabella 



This plant, so characteristic of the rim-rock crevices especially 

 on the more moist exposures, also occurs rather frequently 

 (often 2 or 3 per square meter) on moist slopes in the prairie. 

 The tufted radical leaves mostly remain green all winter. It 

 belongs to the estival aspect. An examination of seven plants 

 gave an average root depth of 5 feet and 1.4 inches. One root 

 reached a depth of 5 feet and 11 inches. The strong tap is 

 triangular in section near the top and often retains this shape 

 to a depth of 2 feet. The laterals, which are quite numerous, 

 usually come off in the first foot of soil. The root-system as a 

 whole is poorly branched, even the root tips are poorly supplied 

 with branches. 



Leptotaenia multifida 



This large, much branched, umbelliferous plant occurs quite 

 commonly on both dry and moist hillsides. The great ternately 

 decompound, pinnatifid leaves, together with the main stems 

 which stand up well above other prairie vegetation, are very 

 conspicuous even when the plants are not abundant, and especi- 

 ally so in June, when after flowering, the leaves turn yellow be- 

 fore drying up. 



Fourteen root-systems were examined, mainly incidentally 

 while excavating other roots. These large fleshy roots are some- 

 times 7 inches in circumference and may reach a depth of 5 feet 

 and 7 inches. The fusiform roots may narrow down gradually 

 or rather abruptly, even to a diameter of one or two millimeters 

 and then again enlarge at a greater depth to a size equalling the 

 original. This is sometimes repeated several times, thus giving 



