Giant Reed

Arundo donax

Management Options

Mechanical/Physical Control Options

Giant reed can be cut and the rhizomes can be dug up but physical control is difficult because it can reestablish from any remaining rhizomes. Burning followed by herbicide treatment is effective on Arundo.

Biological Control Options

There is no known biological control for giant reed.

Chemical Control Options

The active ingredients that have been most successful in treating giant reed are glyphosate (G), triclopyr (G), imazamox (G), and imazapyr(E). E = excellent, G = good

Rodeo, Aquamaster, Eraser AQ, Touchdown Pro, and AquaNeat are liquid glyphosate formulations that have been effective on this plant. Glyphosate is a broad spectrum, systemic herbicide. Systemic herbicides are absorbed and move within the plant to the site of action. Systemic herbicides tend to act more slowly than contact herbicides. An aquatically registered surfactant (see the label) will have to be added to some of these formulations for good results.

Clearcast is a liquid imazamox formulation. It is a broad spectrum, systemic herbicide. Systemic herbicides are absorbed and move within the plant to the site of action. Systemic herbicides tend to act more slowly than contact herbicides. An aquatically registered surfactant (see the label) is needed for application.

Habitat is an liquid imazapyr formulation. It is a broad spectrum, systemic herbicide. Systemic herbicides are absorbed and move within the plant to the site of action. Systemic herbicides tend to act more slowly than contact herbicides. An aquatically registered surfactant (see the label) is recommended for good results.

One danger with any chemical control method is the chance of an oxygen depletion after the treatment caused by the decomposition of the dead plant material. Oxygen depletions can kill fish in the pond. If the pond is heavily infested with weeds it may be possible (depending on the herbicide chosen) to treat the pond in sections and let each section decompose for about two weeks before treating another section. Aeration, particularly at night, for several days after treatment may help control the oxygen depletion.

One common problem in using aquatic herbicides is determining area and/or volume of the pond or area to be treated. To assist you with these determinations see SRAC #103 Calculating Area and Volume of Ponds and Tanks.

Many aquatically registered herbicides have water use restrictions (See General Water Use Restrictions).

To see the labels for these products click on the name. Always read and follow all label directions. Check label for specific water use restrictions.

Cultivation Options

Giant reed can be propagated by transplanting the rhizomes during late winter. Giant reed can be an aggressive invader and should not be planted where it can take over riparian or wetland areas.