Sago pondweed seeds form terminal clusters, distinguishing it from horned pondweed and widgeon grass. Water Celery (Vallisneria americana) also known as eel-grass has long ribbon-like leaves that emerge in clusters. Sago pondweed seeds are in terminal clusters. Pros and Cons of Sago Pondweed. This plant can create dense stands that clog irrigation canals and produce major problems for water flow and access, but it is very important in natural habitats as a waterfowl food source. The seeds are also distinctly different among the three species. Sago pondweed is generally completely submersed except the reproductive stalk that peaks above the water that flowers June – September. Fish it with a rattle-trap, big swim bait or Carolina rig that will float just above emerging plants. Be careful not (parseInt(navigator.appVersion) >= 3 )) || cup into the water. The Sago Pondweed solves that predicament by having a second name: f ennel-leaf pondweed. // -->