RICHARDSON PONDWEED 



Potamogeton Richardson ii Rydb. 



Richardson pondweed is usually found growing in deeper water of 

 lakes and slower moving streams. It has occasionally been observed in 

 large irrigation canals, but is seldom reported as being a serious 

 problem to water distribution systems. 



This species has vegetative characteristics resembling those of two 

 other pondweed species {P. praelongus and P. perfoliatus) that grow 

 in similar habitats, and it may be a hybrid from these species. The leaf 

 and stem growth characteristics of Richardson pondweed are quite 

 distinct. The leaves of this plant are somewhat oval to linear, being 

 thin and membraneous and clasping the stem at point of attachment 

 (insert 1). All leaves are submersed and become progressively shorter 

 toward the tip of a branch. Leaves have wavy margins and exhibit three 

 to seven prominent veins that tend to parallel the long axis of the leaf. 

 Stems and rhizomes are white and not spotted. Vegetative 

 reproduction is from slender, fleshy winter-buds that develop under 

 the soil on the terminals of horizontal stems (insert 2). These 

 overwintering structures resemble those produced by American 

 pondweed, but outwardly appear to be less scaly and are more fleshy 

 and white in color. 



Flowers are borne on spikes that are produced near the water 

 surface and may emerge. The beaked, nutlike fruits are produced on 

 the flower spikes similar to American pondweed. 



This plant is widespread across the northern part of North 

 America. 



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