P. pungens. Table Mountain P.; N. J. to Ga. 
P. resinosa. Red P.; N. S. to Pa. and Mich. 
P. rigida. Pitch P.; N. B. to Ga. 
P. Sabiniana. Digger P.; Calif. 
P. Strobus. White P.; Newf. to Ga. and Iowa. 
P. S. fastigiata. 
P. S. nana. 
P. sylvestris. Scots P.; Eu. to Siberia. 
P. s. argen tea. 
P. s. rigensis. 
P. s. Watereri. 
P. tabulaeformis. Chinese P.; N. to W. China. 
P. Taeda. Loblolly P.; N. J. to Fla. and Tex. 
P. Thunbergii. Japanese Black P.; Japan. 
P. Torreyana. Soledad P.; S. Calif. 
P. virginiana. Scrub P.; N.Y. to Ga. and Ohio. 
P. yunnanensis. W. China. 
PLATANUS, Platanaceae. Plane-tree. Often planted as street 
trees, particularly P. acerifolia. The trunks are showy when the 
outer layer of bark flakes off in late summer [7B]. 
P. acerifolia (P. occidentalis x orientalis). London P. 
P. occidentalis. Buttonwood; Me. to Fla. and Tex. 
P. orientalis. Oriental P.; W. Asia and S.E. Eu. 
POLYGONUM, Polygonaceae. P. Auberti is a vigorous, white- 
flowered vine. P. vaccinifolium is a prostrate subshrub that has 
attractively colored foliage in the fall [5E, nursery]. 
P. Auberti. Silver lace-vine; W. China. (Jy-S.). 
P. vaccinifolium. Himal. 
PONCIRUS, Rutaceae. Interesting because of its green stems, 
large green spines, and its flowers and fruits which resemble 
those of the true orange [6F]. 
P. trifoliata. Hardy Orange; N. China, Korea (My.). 
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