Learn more about Reed Canary Grass
It is a major threat to marshes and natural wetlands because of its hardiness, aggressive nature and rapid growth. Native wetland and wet prairie species are replaced after several years of reed canary grass presence. It is of particular concern because of the difficulty of selective control.
Fire can help control the spread of reed canary grass and keep it out of high quality wetlands. Repeated late autumn or late spring burning for several years can control this species. Annual burning may be needed for 5-6 years before good control is apparent. Burning is most effective where other species are present or in the seed bank, since fire allows native, fire-adapted species to compete successfully. Fire is not very effective in dense monocultures of this grass where seeds or plants of native species are absent.
The native reed canary grass should not be totally eliminated, but no reliable method for telling the difference between the forms is known. Control measures should be implemented when reed canary grass degrades the natural quality or diversity of a community.
Prescribed fire as described above should be used in areas that will burn. Hand removal for control may be feasible in small stands. There is evidence that hand chopping the stems at flowering time may kill small clones. Certain herbicides are effective where there is no real concern for damage to surrounding native species. According to label recommendations, Rodeo, a formulation of glyphosate designed for use in wetlands, will kill reed canary grass, especially young plants, when applied to foliage. Rodeo should be applied in early spring when reed canary grass is green and most native wetland species are still dormant. The area should be checked after spraying, and any surviving reed canary grass should be sprayed the following spring. Dalapon and Amitrol also reportedly kill canary grass, although no treatment recommendations other than label recommendations are available. All three herbicides are licensed for use in aquatic areas. Rodeo and Amitrol are nonselective herbicides that will kill all vegetation contacted. Dalapon selectively kills grasses and monocots, but not broadleaf plants. Spraying foliage with Roundup (a formulation of glyphosate) mixed according to label instructions and subsequent burning of dead residue has been moderately effective in northern Illinois. However, Roundup is not licensed for use in aquatic areas and should only be used in areas without standing water. When using any herbicide, precautions should be taken to avoid contacting non-target species. Do not spray so heavily that herbicide drips off the target species. The herbicide should be applied while backing away from the treated area to avoid contacting wet herbicide. By law, herbicides only may be applied as per label instructions. Herbicide caution: There are probably no herbicides that are selective enough to be useful and efficient in high quality natural communities, unless applied with extreme caution where only minor spot treatments are needed.
Where practical, it can be useful to sow in seed of nearby native grasses and forbs after reed canary grass has died (due to control efforts) or gone dormant. Seed of nearby native grasses and forbs should be collected when ripe and then raked into the sod as soon as the reed canary grass has died.
The following practices should be avoided: