PRAIRIE PLANTS OF SOUTHEASTERN WASHINGTON 285 



course and branch profusely all the way to the tip, sending off 

 laterals seldom over 3 inches long but branched to the fifth 

 order. The roots are jet black. Eleven plants were examined 

 on a northeast slope and an average root depth of 4 feet and 8.6 

 inches was determined. 



Sidalcea or eg ana 



This mallow is confined to north hillsides and low ground. 

 While much less abundant than Geranium viscosissimum , it is 

 similar in habit in exposing a great number of large leaves. 

 This plant may reach a height of over 3 feet. It blossoms 

 later than Geranium but like it retains green foliage until frost. 



Only two root-systems were examined. In both numerous 

 strong laterals were thrown off within 4 inches of the surface. 

 At 24 inches the tap broke up into three nearly equal parts, the 

 largest and longest part reaching a depth of only 3 feet and 1 

 inch. The other plant reached a depth of 4 feet and 1 inch. 

 Sidalcea roots cannot easily be confused with others for they 

 send off small laterals in groups ranging from 3 to 8 in a group. 

 This is most pronounced in the older parts of the roots. Often 

 where a big lateral comes off one or more little ones originate 

 with it. These groups of small laterals are usually less than 2 

 inches in length. 



Hier actum scouleri (Fig. 17) 



The Hawkweed, with its densely hairy clusters of basal leaves, 

 and its similarly leaden colored cauline leaves and stems reaches 

 a height of about two feet. The rather small yellow flowers 

 appear late in June and blossoming continues until August, 

 even after the basal leaves have dried and turned brown. It 

 is an important prairie species. 



Twenty-six root-systems were examined. They gave an 

 average depth of 5 feet and 4.3 inches. Hieracium sends out 

 numerous roots, — as many as 50 from a single inch of its corymb — 

 which in turn is from 8-12 inches long. None of these roots 

 are over 3 millimeters in diameter. They pursue a nearly 



