Southeastern Washington and Adjacent Idaho. 113 



not reported for the region were encountered. Among these the 

 occurrence of the devil's club, Echinopanax horridum, along cer- 

 tain streams in Thatuna Hills, is especially interesting. Many 

 of the species new to the region are ruderals. Other plants like 

 Crataegus columbiana piperi, heretofore known to occur only in 

 Washington, were also repeatedly found in Idaho. 



It is hoped that the results of the present research may form 

 a basis for further investigation of the ecological problems of 

 this and adjoining regions. 



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