- 52 - 



alkalinity: mean 68.6 mg/1; range 20.0-123.5 mg/1 

 pH: mean 8.3; range 6.8-10.6 



30. Potamogeton pr aelongus Wulfen Fig. 34, Map 34 



Locally abundant, usually in deep waters of moderate alkalinity 

 in New England. Range extends from Labrador west to Alaska, 

 south to New Jersey, Ohio, Indiana, Colorado, Utah, and 

 California. 



Rare and endangered plant list: New Hampshire 



alkalinity: mean 47.2 mg/1; range 8.0-123.5 mg/1 

 pH: mean 7.7; range 6.7-9.8 



31. Potamogeton r ichardsonii (Benn.) Rydb. Fig. 35, Map 35 



Locally abundant in northern Maine and western New 

 England; sporadic elsewhere. Often confused with P. 

 perfoliatus with which it may hybridize. Range extends from 

 eastern Quebec west to Alaska, south to New England, New York, 

 Pennsylvania, Indiana, Iowa, Colorado, Utah, and California. 



Rare and endangered plant list: New Hampshire, however, 

 specimens from New Hampshire have since been reidentified as P. 

 perfol iatus and the taxon does not occur in that state. 



alkalinity: mean 46.0 mg/1; range 13.5-111.5 mg/1 

 pH : mean 7.6; range 6.7-10.2 



32. Potamogeton perfoliatus L. Fig. 36, Map 36 



Common in New England in acid, alkaline and saline 

 coastal waters. In New England, leaves become more lanceolate 

 in acid waters and more orbicular in saline waters. Populations 

 in the United States have been referred to var. bupleuroides 

 (Fern.) Farwell. Haynes (pers. comm.) has observed 

 morphological variation in the taxon from north to south, but 

 since the variation is clinal, lacking discontinuity, no 

 additional taxa have been recognized. Range extends from 

 Newfoundland to Ontario, south to North Carolina, Alabama, and 

 Louisiana; most abundant along the coast. 



alkalinity: mean 47.2 mg/1; range 8.0-123.5 mg/1 



pH: 7.7; range 6.7-9.8 



chloride: mean 135.1 mg/1; range 1.6-4095.0 mg/1 



