A GUIDE TO THE WILD FLOWERS 103 



6-12 in. tall, with a somewhat 4-angled stem, a little rough 

 at the joints. Leaves broadest towards the middle, tapering 

 at both ends, ys-i in. long, about a fourth as wide. Sheaths at 

 the leaf base thread-like at the top. Flowers a few, in small 

 clusters from among the leaves, green. In dry soil and often 

 a weed, Ontario to Georgia and westward. August. Other 

 Knotweeds are Nos. 270 and 299, and there are additional 

 species distinguished by technical differences. 



297. Prince's Feather. Persicaria orientaUs. {Polygonum 

 orientale.) A tall annual, 2-6 ft. high, with an erect, usually 

 branched rough-hairy stem. Leaves alternate, oval or broadly 

 oblong, more pointed at the tip than at the base, 3-8 in. long, 

 and about half as wide. Flowers red or crimson, in drooping, 

 finger-shaped clusters. August. Often cultivated and fre- 

 quently escaping to waste places throughout eastern North 

 America. Native of India. 



298. Lady's Thumb. Persicaria Persicaria. (Polygonum Per- 

 sicaria.) A smooth or faintly hairy plant, 8-20 in. high, with 

 conspicuously dotted leaves which are often blotched. Leaves 

 lance-oblong, essentially stalkless, narrowed towards the tip 

 and base, 2-5 in. long, and about one third as wide. Flowers 

 in finger-shaped erect clusters, pinkish. One of the com- 

 monest weeds throughout North America on waste or cul- 

 tivated land. Native of Europe. June-October. Fig. 298. 

 There are several relatives, distinguished by technical char- 

 acters, besides Nos. 297 and 299. Other closely related 

 plants are Nos. 260 and 961. 



299. Japanese Knotweed. Pleuropteriis Zuccaritiii. (Poly- 

 gonum cuspidatnm.) An erect or arching, usually branched 

 herb, 4-8 ft. tall, with a smooth or scurfy stem and alternate 

 leaves distinctly marginally veined. Leaves broadly oval, 

 short-stalked, 3-5 in. long, rather abruptly narrowed at the 

 tip, and broad at the base. Flowers greenish-white in loose, 



pen, much-branched usually terminal clusters. Cultivated, 

 • A\(\ sometimes escaping to fields and waste places. Native of 

 Japan. July-October. 



300. Field Sorrel. Rumcx Acetosella. A smooth herb not 

 over 12 in. high with arrowhead-shaped leaves, both basal 

 and on the stem. Foliage bitter and used for greens by some. 



