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JOHN ERNST WEAVER 



Sieversia ciliata 



The soft hairy, tufted, radical leaves of Sieversia often remain 

 green throughout the winter. The simple erect stems reach a 

 height of 12-18 inches and bear their blossoms in late May or 

 early June, while in late July or the first of August the aerial 





Fig. 15. Fig. 16. 



Fig. 15. Root-system of Helianthella douglasii. It may be noted that the tap 

 root was decayed. 



Fig. 16. Hoorebekia racemosa. This specimen had no large laterals. 



plant parts largely dry up. This is a common, abundant, and 

 cosmopolitan prairie species. 



Few roots of Sieversia penetrate beyond depths of 5 feet and 

 6 inches. It sends out as many as 20-30 roots from a single 

 inch of its thick rootstock. None of these roots are over 3-4 

 millimeters in diameter. They pursue a vertically downward 



