98 



POLYGONACEAE (BUCKWHEAT FAMILY) 



ERECT KNOTWEED 

 Polygonum erectum, L. 



Native. Annual. Propagates by seeds. 

 Time of bloom: July to September. 

 Seed-time: August to October. 



Range: Ontario to the Northwest Territory, southward to Ten- 

 nessee and Arkansas. 

 Habitat: Yards, waysides, and waste places. 



A plant resembling the Doorweed and often growing in company 

 with it, but having larger leaves and flowers and standing erect at 

 a height of four inches to a foot or more. Stem 

 slim, round, smooth, yellowish green, with 

 many branches. Leaves broader than those 

 of the Doorweed, one-half inch to an inch 

 long, elliptical, usually obtuse, sessile or with 

 very short petioles ; stipules funnel-shaped, 

 paper- white, often torn and ragged. Flowers 

 greenish white, in small axillary clusters, on 

 pedicels usually about as long as the sheathing 

 stipules ; stamens five or six. Achenes dull 

 brown, pointed ovoid, enclosed in the per- 

 sistent calyx-lobes. (Fig. 58.) 



Means of control 



Prevention of seeding by close cutting or 

 erectum). x i pulling while in early bloom. 



BUSHY KNOTWEED 



Polygonum ramosissimum, Michx. 



Native. Annual. Propagates by seeds. 



Time of bloom : July to September. 



Seed-time: August to October. 



Range : Maine to New Jersey on the Atlantic Coast ; in the West 



from Minnesota to the Northwest Territory, California, Arizona, 



and New Mexico. 

 Habitat : Sandy, often brackish, soil ; irrigated lands, waste places. 



