April 1, 1916 383 



Polygonum [Tonm.] L. Knotweed. 



Polygonum aviculark h. 4. Knotgrass; doorweed. Coir, 

 mon about door yards and waste places everywheie. Natural- 

 ized from Europe. May to October; o-reen with pink border. 



Polygonum spkrgulariaeformk Meisner. i. Spurry 

 knotweed. Infrequent in sandy places, Lower Albina. May to 

 October; pink with green uiidveins. 



Polygonum polygaloides Meisner i. Milkwort knot- 

 weed. Infrequent in depressions, Tulatin Plains. June to Sep- 

 tember, White to pinkish. 



BiLDERDYKiA Dumont. 



BiLDERDYKiA CONVOLVULUS (L) Dumont. r. Black bind- 

 weed. {^Polygonum Cotivolviilus L.) A troublesome weed, not 

 uncommon in cultivated fields, gardens and waste places around 

 Portland. Naturalized from Europe. June to September. Green 

 or whitish. 



Rumex L. Dock, sorrel. 



RuMEX ACETOSELLA L. 4. Sheep sorrel. A common weed 

 ill fields, roadsides and waste places everywhere. Naturalized 

 fiom Europe. May to September. Staminate yellowish, pis- 

 tillate reddish. 



RuMEX OCCIDENTALIS Wats. 4. Western dock. Not un- 

 common in moist woods, Swan island, Ross island, etc. May to 

 September. Rosy red. 



RuMEX CRISPUS L. 4. Curly dock. Common in yards, 

 cultivated ground and waste places about Portland. Naturalized 

 fram Europe. May to August. Greenish. 



X RuMEX MARICOLA Remy. 4. Chile dock. On ballast 

 grounds and waste places, Lower Albina. Adveutive from Chile, 

 May to August. Greenish. 



RUMEX SALICIFOLIUS Weium. 4. Willow leaved dock. In- 

 frequent on bottom lands near Milwaukee. May to September, 

 Pink-red. 



Rumex obtusifolius L. 4. Broad leaved dock. On bot- 

 tom lands, Mock's Bottom and about Vancouver. Naturalized 

 from Europe, May to August. Greenish, 



