146 BOTANY OF MICHIGAN 



URTICACEAE. Nettle Family 



Ulmus americana L. American elm. Frequent throughout, especially 

 along streams. Often with beech and maple, and many trees large. 



Urtica gracilis Ait. Slender nettle. Occasional throughout in moist 

 open or slight ly shaded ground. 



SANTALACEAE. Sandalwood Family 



Comandra richardsiana Fernald. Richards' toadflax. T>ry sandy 

 ground throughout. Often abundant. 



Comandra livida Richards. Northern comandra. In dry sandy ground 

 near Vermilion. Apparently infrequent. Probably overlooked. 



POLYGONACEAE. Buckwheat Family 



Rumex britannica L. Great water dock. Wet swampy mostly open 

 places throughout. Common near Vermilion on border of tamarack- 

 black spruce swamps. 



Rumex crispus L. Yellow dock. In cultivated and waste grounds 

 throughout. Common. 



Rumex obtusifolius L. Bitter dock. As a weed in cultivated grounds. 

 Infrequent. 



Rumex aeetosella L. Field sorrel. Frequent as a weed near dwellings 

 and cultivated grounds. 



Polygonum aviculare L. Knot-grass. About dwellings and in culti- 

 vated grounds as a weed. Frequent. 



Polygonum erectum L. Erect knotweed. Only as a weed in waste 

 places, cultivated grounds and about dwellings. Not common. 



Polygonum ramosissimum Michx. Bushy knotweed. Abundant in a 

 clearing north of Eckerman, appearing to be introduced. 



Polygonum lapathifolium L. Pale persicaria. Occasional about farm 

 buildings and in cultivated grounds, appearing to be introduced. 



Polygonum amphibium L. Water persicaria. Along streams and 

 ponds throughout. Plentiful. 



Polygonum hydropiper L. Common smartweed. Damp open or 

 slightly shaded ground throughout. Often plentiful. 



Polygonum persicaria I;. Lady's thumb. Occasional as a weed about 

 farm buildings and in cultivated grounds. 



Polygonum sagittatum L. Arrow-leaved tear-thumb. Damp or 

 swampy places, open or slightly shaded throughout. Frequent. 



Polygonum convolvulus L. Black bindweed. As a weed in gardens 

 and cultivated grounds. Not abundant. 



Polygonum cilinode Michx. Fringed black bindweed. Open dryish or 

 damp ground throughout. Abundant in spots. 



