Weed Identification


Welcome to SePRO's Aquatic Weed Identification Guide. This guide will serve as your first step toward identifying and managing your aquatic weed problem. To get started, click on whichever group of aquatic weeds to which you feel your problem weed belongs and work through the examples until you find it.



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Sagittaria lancifolia

Arrowhead is a shallow aquatic weed with leaves that are shaped like an arrow. (They also resemble a wishbone.) Leaves are above the water most of the time, but can sometimes be submersed or floating. Arrowhead has distinct veins that can be seen on leaves that arise from a common point. The flowers and fruit are produced on leafless stems. These may reach 1.5-3 feet tall. Flowers have three sepals and three white petals. The petals are 8-14 mm long. The root system resembles a bulb.

Also known as: Lance-leaved arrowhead; broadleaf arrowhead; duck potato


Utricularia spp.

Bladderworts are submersed free-floating plants. There are about 200 species in the world, ranging in size from a few inches to several feet long. Tiny bladders attached to the leaves trap and digest very tiny animals. Utricularia species occurs almost always (estimated probability 99%) under natural conditions in wetlands. All bladderworts are rootless. They have main stems from which lacy, often complex leaves grow. Bladderwort flowers are usually bright yellow (but sometimes lavender, depending on species); the flowers have two "lip-like" petals of about equal size. Flowers are on long stalks that emerge several inches above the water. The carnivorous bladders are attached at regular intervals along the linear leaf segments.

Also known as: Common bladderpod; greater bladderwort; hooded watermilfoil; popweed


Scirpus spp.

Bulrushes grow in shallow water and moist soils, so shorelines of ponds provide a great habitat for these plants. Some may reach 8 - 10 feet in height. Some bulrush species have three sided stems like sedge. Leaves grow on the lower stems and irregular seed clusters are densely packed located near stem tips.

Also known as: Scirpus



Cattails have dense, "sausage-like," spikey flowers, called the catkins that appear on top of the long, slender stems in late summer to early fall. Cattails can be partially submerged or in boggy areas with no permanently standing water and can grow to 5 or 10 feet in height. They provide a wildlife habitat and refuge. Overgrowth can choke off open water, driving away birds.

Also known as: Tullies