557 



BUCKWHEAT FAMILY. 



6. Polygonum incarnatum Ell. Slender 

 Pink Persicaria. (Fig. 1323.) 



]\>l\'Xonnm incarnatum Kll. Bot. S. C. & Ga. I: 456. 1817. 

 Annual, glabrous or nearly so, stem erect, simple 

 or branched above, more or less swollen at the nodes, 

 2-4 tall. Leaves lanceolate, 3 / ~9 / long, J^'-i^' 

 wide, acuminate at both ends, short-pctioled, sparingly 

 punctate and ciliate; ocreae cylindric, long, loose, 

 brittle, sometimes ciliolate when young, glabrous when 

 mature; racemes panicled, drooping, \]&'-4, f long, 

 linear, many-flowered; calyx white or pink, small, 

 5-parted; stamens 6; style 2-parted to near the base; 

 achene ovoid-oblong, lenticular, about i // long, flat or 

 biconcave, smooth, shining. 



In wet soil, Vermont to Illinois, south to Florida and 

 Louisiana. June-Sept. 



7. Polygonum lapathifolium L. Dock- 

 leaved or Pale Persicaria. (Fig. 1324.) 



Polygonum lapathifolinm L. Sp. PI. 360. 1753. 



Annual, stem simple or much branched, erect or as- 

 cending, swollen at the nodes, i-3 high, the pedun- 

 cles and pedicels glandular. Leaves lanceolate or ob- 

 long-lanceolate, 2 / -io / long, usually broader than 

 those of the preceding, attenuate to the apex, acumi- 

 nate at the base, short-petioled, ciliate, inconspicuously 

 punctate; ocreae cylindric, ribbed or striate; racemes 

 panicled, i'-4' long, drooping, narrow, rather dense; 

 calyx pink, greenish or white, 5-parted; stamens 6; 

 style 2-parted to below the middle; achene broadly 

 oblong or ovoid, lenticular, \" long, brownish or black, 

 slightly reticulated but shining, its faces concave. 



In waste places, throughout temperate North America. 

 Naturalized frons Kurope. Sometimes a troublesome 

 weed. Native also of Asia. June-Sept. 

 Polygonum lapathifolium nodosum (Pers. ) Small, Mem. Torr. Club, 5: 140. 1894. 

 Polygonum nodosum Pers. Syn. i: 440. 1805. 



Generally robust and glabrous; stem stout, reddish, purple spotted and with a purple ring be- 

 low each ocrea, much thickened at the nodes; leaves conspicuously punctate; racemes I'-j' long, 

 less drooping, often erect; achene slightly larger. Occasional in the range of the type. 



Polygonum lapathifolium incanum (Schmidt) Koch, Syn. Fl. Germ. 711. 1837. 

 Polygonum incanum Schmidt, Fl. Boern. 4: 90. 1795. 



Low, stem slender, erect, 2'-i2' high, slightly scurfy; leaves lanceolate, ovate or oblong, usu- 

 ally narrowed at the base, white-tomentose beneath, glabrous above; racemes S'-iJ4' long. In 

 waste places, Nova Scotia to Ontario, New York and British Columbia. 



8. Polygonum Pennsylvanicum L. 



Pennsylvania Persicaria. (Fig. 1325.) 

 Polygonum Pennsylvanicum L. Sp. PI. 362. 1753- 



Annual, glabrous below ; stem erect, simple or 

 branched, i-3 tall, the upper parts, the peduncles 

 and pedicels glandular. Leaves lanceolate, acumi- 

 nate at the apex, petioled, ciliate, 2 / -ii / long, the 

 upper sometimes glandular beneath; ocreae cylin- 

 dric, thin, naked, glabrous; racemes panicled, erect, 

 thick, oblong or cylindric, dense, i / -2 / long; calyx 

 dark pink or rose-color, 5-parted; stamens 8 or fewer; 

 style 2-cleft to about the middle; achene orbicular or 

 mostly broader than high, i%" long, short-pointed, 

 lenticular, smooth, shining. 



In moist soil, Nova Scotia to Ontario, Minnesota, 

 Florida and Texas. Ascends to 2000 ft. in Virginia. 

 July-Sept. 



