Swamp stonecrop (Crassula helmsii)

Description: Available in some areas as an oxygenating plant for water gardens and aquaria.

Habit: Aquatic or semi-terrestrial evergreen; succulent perennial that may form a carpet at waters edge, or grow completely submerged in deeper water.

Leaves: Opposite and narrow, 4-24 mm (0.16-0.94 in) long.

Stems: Elongated; stiff.

Flowers: Tiny, white in color, 4 petals.

Fruit and seeds: Fruits are follicles containing 2-5 elliptical and smooth seeds about 0.5 millimeters long.

Habitat: Native to Australia and New Zealand. Found in water bodies with still or slow-moving water; tolerates alkaline, acidic, or slightly salty water.

Reproduction: May be spread by tiny stem fragments; seeds are not known to be produced.

Similar species: Water pygmyweed (Crassula aquatica).

Monitoring and rapid response: Hand-pulling, grass carp, Diquat alginate has been the most effective herbicide.

Credits: The information provided in this factsheet was gathered from the Invasive Species Specialist Group, the Michigan Natural Features Inventory and Oregon State University.

Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org).Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).

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