Sparganium eurycarpum giant bur-reed Sparganiaceae SPEU; Bx, pb; Q, cr (extirpated?); R, lp;

 

Sparganium eurycarpum.Arthur Haines.New England Wild Flower Society.gobotany.newenglandwild.org

Sparganium eurycarpum. Copyright © 2015 Arthur Haines.New England Wild Flower Society.gobotany.newenglandwild.org (Accessed 4/2014).

Sparganium eurycarpum is an emergent aquatic perennial monocotyledon herb, to 1.8 m tall; colonial from rhizomes rooted in mud. 

Leaves to 80 cm long 2 cm wide, cat-tail-like but more yellow green, midrib prominent, stiff, keeled in back. 

Flowers very similar to Samericanum, green, female flowers with 2 stigmas, in stalkless, ball-shaped, spiky clusters, male flowers in smaller clusters above females along inflorescence stems about 2-3 cm wide, at base of zigzag stem above a leaf-like bract. 

Fruit dry achenes, reverse-pyramidal-shaped (obconical), widest at top, hard. 

Wetland status: OBL. 

Frequency in NYC: Very infrequent. 

Origin: Native. 

Habitat: Edges of open ponds in shallow water.