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Pontederia (Pickerel-weed) 



Emergent plants of muddy or sandy shores of lakes, ponds, and 

 streams. Perennial, growing from creeping rhizomes; leaves basal, 

 erect, long-petioled, usually cordate; flowers violet-blue, in a dense 

 spike with spathe-like bract; fruit a utricle crested with six toothed 

 ridges. 



1. Pontederia cordata L. Figs. 11, 12, Map 21 



Extremely common along shores of lakes, ponds and streams 

 throughout New England. The seedlings consist of submersed rosettes 

 of linear leaves and often have one or two petiolate, slightly lanceolate 

 leaves. Lowden (1973) recognizes a variety with narrow to broadly 

 lanceolate leaves, var. lancifolia (Muhl.) Torr., whose range in North 

 America is chiefly southern Coastal Plain. The range of variability in 

 the leaves of this species is considerable and we question the 

 occurrence of var. lancifolia in New England. Range extends from 

 Nova Scotia west to southern Quebec, southern Ontario, Michigan, 

 Wisconsin, and Minnesota, south along the coast to Florida, Alabama, 

 Mississippi, Louisiana, and Texas; widely scattered throughout the 

 other eastern states; greatest numbers in the coastal and Great Lakes 

 states. 



alkalinity: mean 20.3 mg/1; range 2.5-111.5 mg/1; (65) 

 pH: mean 7.0; range 5.0-8.9; (61) 



Heteranthera (Mud-plantain) 



Emersed or submersed plants of muddy shores, streams, and quiet 

 waters; growing from rhizomes or with fibrous roots; stems often 

 rooting at nodes; flowers blue, white, or yellow, emerging from the 

 sheathing leaf bases; leaves alternate or in a basal rosette; fruit a 

 capsule. 



Key to Species 



1. Leaves lax, long-linear, sessile (fig. 13A,B), usually submersed; 

 flowers yellow; stamens unequal, anthers ovate, 2 yellow, 1 greenish. 



\. H. dubia 



1. Leaves erect, reniform to cordate (fig. 14), petiolate, usually emersed; 

 flowers white or pale blue; stamens equal, anthers sagittate, all 3 

 yellow. 

 2. H. reniformis 



