188 BOTANY OF MICHIGAN 



Rumex acetosella L. Field sorrel. Sheep sorrel. A common weed, 

 especially in old fields. 



Polygonum avicvlarelj . Knotgrass. Door-weed. Common as a weed 

 in yards, fields and along roads. 



Polygonum erectum L. Erect knotweed. Common as a weed in yards 

 and waste places. 



Polygonum lapathifolium L. Slender pink persicaria. Frequent in 

 wet places, especially near the small lakes, and often a weed in gardens 

 and cultivated fields. 



Polygonum amphibium L. Water persicaria. Common about ponds 

 and small lakes in very wet places. Often in shallow still water, when in 

 general appearance it much resembles a pond weed. 



Polygonum muhlenbergii (Meisn.) Wats. Swamp persicaria. In very 

 wet places and often in water near and about the small lakes. 



Polygonum pennsylvanicum L. Pennsylvania persicaria. Common in 

 moist open or shaded ground. 



Polygonum hydropiper L. Common smartweed. Frequent in moist- 

 open or shaded ground. 



Polygonum acre HBK. Water smartweed. Common in wet places 

 about the small lakes and along the low grassy banks of small streams. 



Polygonum orientate L. Prince's feather. Occasionally escaping 

 from cultivation to roads and near-by fields. Often a weed in gardens. 



Polygonum persicaria L. Lady's thumb. Frequent in damp places, 

 along banks of ditches, and often a roadside weed. 



Polygonum hydropiper oides Michx. Wild water pepper. In ditches 

 and in and along small streams. 



Polygonum virginianum L. Virginia knotweed. In rich woods near 

 Murphy's Lake. 



Polygonum sagittatum L. Arrow-leaved tear-thumb. In wet places 

 about Mud Lake southwest of Fostoria. Very probably appearing in 

 many other wet places. 



Polygonum convolvulus L. Black bindweed. Everywhere as a weed in 

 cultivated and waste places. 



Polygonum cilinode Michx. Fringed black bindweed. On sides of 

 dry hills near Cat Lake and Mud Lake. "Dry woods on the east side 

 of Dayton Township." C. A. Davis. 



Polygonum scandens L. Climbing buckwheat. Frequent on borders 

 of woods and thickets, especially in the vicinity of the small lakes. 



Fagopyrum esculentum Moench. Buckwheat. Occasional as an escape 

 along roads, in fields, and about farm buildings. 



Polygonella articulata (L.) Meisn. Coast jointweed. Noticed by 

 Prof. C. A. Davis on sand ridges near the shore of Saginaw Bay. 



