THREADLEAP PONDWEED 

 (Potamogeton filiformis; includes 

 interior) 



Alaska to Greenland, California, 

 Michigan and Pennsylvania. 



Resembles Sago Pondweed but the 

 stems are usually shorter and less 

 branched and the smaller seeds (a little 

 less than 1/8 inch vs. 1/8 inch or more) 

 have a flattish, wartlike tip. Resem- 

 bles Bigsheath Pondweed but is much 

 smaller; all the leaves have narrow- 

 sheathed bases; and the seed heads 

 usually have only 3 or 4 clusters of 

 seeds. 



WESTERN PONDWEED 

 (Potamogeton latifolius) 



Alkali water from Oregon to Texas. 



Has short, ribbonlike, blunt-tipped leaves 

 with bases that make a sheath two or more times the 

 width of the stem. Seed heads and seeds are almost 

 the same as those of Sago Pondweed. 



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