WATERPLANTAIN 



Alisma gramineum var. Geyeri Samuelsson 



Plants in this family can be seen growing emersed, totally 

 submersed, or on wet banks. The species that is illustrated produces 

 both emersed and submersed vegetation. It is probably more 

 commonly observed in irrigation canals as a submersed plant. Possibly 

 when it develops the emersed form, it might be thought of as being 

 a totally different plant. 



In a submersed habit this plant produces long linear or grasslike 

 leaves for which the specific name gramineum , or grasslike, is 

 descriptive. The leaves arise from the base or crown, attaining lengths 

 up to 900 millimeters. Roots of Alisma are fibrous and generally do 

 not extend deep into the mud. In the emersed habit, the narrow, 

 elliptical-shaped leaf blades emerge above the water surface supported 

 by long, firm petioles (leaf stems). 



Flowers of this plant are borne on a loose, irregular forked 

 arrangement or loose panicle. Flower petals are white to purplish. The 

 individual seed heads or nutlets are borne in a ring (insert 1). 

 Differentiation between varieties of this species is made by the length 

 of the fruiting stems, Ce/e/v having fruiting stems shorter than the 

 leaves. 



Alisma may be annual or perennial. These plants produce many 

 viable seed that readily germinate in a wet or submersed situation. 

 However, the seedling survival is generally low as apparently only a 

 fraction of the germinated seedlings are able to reach maturity. 

 Waterplantain overwinters by means of a fleshy crown or cormlike 

 structure when exhibiting perennial growth habits. 



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