CABOMBACEAE 



1. Submersed leaves opposite, dissected into linear segments (fig. 1); 

 floating leaves small, inconspicuous, oblong to linear-elliptic, pel- 

 tate, less than 2 cm long, subtending flowers (fig. 1); submersed 

 portions of plants lacking mucilaginous coating; flowers white to 

 pinkish; stamens 3-6. 

 1. Cabomha 



1. Submersed leaves absent, except on young plants, then alternate 

 (fig. 2B); floating leaves prominent, peltate, elliptical, 2-10 cm long 

 (fig. 2); submersed portions of plants typically with a mucilaginous 

 coating; flowers red-purple; stamens 12 or more. 



2. Brasenia 



Cabomba (Fanwort) 



Perennial, arising from short rhizomes with fibrous roots; 

 submersed leaves opposite, petioled, fan-like, with finely dissected 

 divisions; floating leaves alternate, small, oblong to linear-elliptic, 

 peltate; flowers usually solitary, borne in axils of floating leaves; 

 perianth white to pinkish, about 12 mm long; carpels (2-)3(-4), separ- 

 ate; fruit leathery, indehiscent, 3-seeded follicle. 



1. Cabomba caroliniana Gray Fig. 1, Map 1 



Locally abundant and weedy in acidic waters of southern New 

 England. This aggressive weed was first reported in New England 

 from Cranston, Rhode Island in 1933. Herbicides and mechanical 

 harvesting have proven completely ineffective for controlling this 

 species. Range extends from southern New Hampshire and Massa- 

 chusetts west to New York, Pennsylvania, southern Michigan, south- 

 ern Illinois, and Missouri, south to Florida, eastern Oklahoma, and 

 eastern Texas. 



alkalinity: mean 15.8; range 3.5-35.0 mg/1; (13) 



pH: mean 6.5; range 5.9-6.8; (10) 



Brasenia (Water Shield) 



Perennial, arising from creeping rhizomes; all leaves floating 

 (submersed leaves present only on young plants), elliptic, peltate; 

 submersed parts typically covered with a thick, mucilaginous coat- 

 ing; flowers solitary, axillary; perianth red-purple, 12-20 mm long; 

 carpels 4-10, separate; fruit a leathery, indehiscent, 1-2 seeded follicle. 



