Polygonum POLYGONACEAE Ramex 



18. Polygonum cuspidatum Sieb. & Zucc. ^^ (Hu Chang; Tiger Stick) (G.M. 589). 

 Bushy herb, to 2m., fls. white, VI-IX; fr. IX-X. Japan, China; locally in An., 

 Ki., Ku. Pond margins and ditch banks. 



19. Poljgonum fagopyrum Linn. {Fagopyrum esculentum Moench) Buckwheat MM 

 (Ch'iao Mai) (B.M. 349; G.M. 589). Erect annual, to lm.; fls. pink or white, 

 V-IX; fr. brown, VIII-IX. Eurasia; locally in An., Ki., Ku. Cultivated for its 

 "grain ". 



3. Rheum Linn. j\MM (Tai Huan Shu; Great-yellow Genus) 



Stout erect perennial herbs with large basal Ivs. and conspicuous ocreae: fls. 

 perfect; stamens mostly 9; styles 3: achenes strongly winged. About 25 species, in 

 Asia; 6 or more in China. (The Greek name.) 

 1. Rheum rhaponticum Linn. Garden Rhubarb (B.M. 349). Stout herb, 1-2 m. high. 



Siberia; locally in Ki., Ku. Cultivated for its fleshy If. stalks which are used 



for food. 



4. Rumex Linn. Dock fflt^kM (Suan Mo Shu) 



Herbs: ocreae not conspicuous: fls. mostly greenish; perianth of 6 segme?its, the 

 outer 3 herbaceous, and the inner enlarged in fr., often bearing a grain-like tubercle; 

 stamens 6; styles 3. 125 species, widely distributed in temperate regions; about 12 

 in China. (The Latin name.) 



Key to the Species 



a. Fls. perfect or polygamous : none of the lvs. hastate. 



b. Valves entire or nearly so, granular 1 . R. patientia 



bb. Valves spiny, fimbriate, or dentate. 



c. Valves spiny, narrowly winged, granular. 



Valves conspicuously reticulate, with a few stout spines; 



granules broadly oblong 2 . R. devtatus 



Valves not reticulate, with many slender spines; granules 



narrowly oblong 3 . R. maritimus 



cc. Valves fimbriate, dentate, or toothed, broadly winged. 



Valves fimbriate or sharply dentate, granular 4. R. japovicus 



Valves pectinately toothed, not granular; teeth often hooked. 5. R. nepalensis 

 aa. Fls. dioecious: at least some of the lvs. hastate. 



Calyx much enlarged in fr., not granular 6. R. acetosa 



Calyx scarcely at all enlarged in fr 7. R. acetosella 



1. Rumex patientia Linn. Patience Dock (G.M. 569). Erect herb, to lm.; fls. V- 

 VI; fr. VI-VIII. Eurasia; locally in An. Roadside weed. 



2. Rumex dentatus Linn. (H.F. 5:59). Erect herb, to lm.; fls. V; fr. VI. Southern 

 and eastern Asia; locally in Ku. Pond margins and ditch banks. 



3. Rumex maritimus Linn. ^KT- (Lien Ming Tzu) (H.F. 5:59). Erect herb, to 

 lm.; fls. VI-VII; fr. V-VII. Eurasia, Africa and the Americas; locally in Ku. 

 Roadside weed. Fig. 76. 



4. Rumex japonicus Meisn. ^|§ (Yang T'i; Goat-hoof) (Mak. F. 630). Coarse herb, 

 to lm; fls. V-VI; fr. VI-VII. Japan, China; locally in Ku. Roadside weed. 



5. Rumex nepalensis Spreng. ^r^ltJfL (Niu Erh Huang Ts'ao; Yellow-cow-colored 

 Herb, (H.F. 5:60) Coarse herb, to 1 m.; fls. VII. Asia, south Africa; locally in Ki. 

 Roadside weed. 



6. Rumex acetosa Linn. Garden Sorrel gtfH (Suan Mu; Sour Sorrel) (G.M. 571). 

 Erect herb, 4-8 dm. high; fls. pink, III-V; fr. IV-VI. Eurasia, North America; 



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