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GREATjU RIVERlRIPW GREENING Reed Canary Grass (Phalaris arundinacea) Description Reed canary grass is a robust cool season grass that is likely circumboreal in origin. Ecotypes and/or cultivars of Eurasian origin were widely planted for use as a forage, conservation plantings, and erosion control, and are likely the aggressive grass that invades and dominates native wetlands and other moist soil habitats throughout Minnesota. Reed canary grass can reach 6 feet in height, but typically lays over, forming a dense mat that smothers native vegetation. The plant is hairless. Leaf blades are % to % inches wide, flat, rough to the touch and blue-green in color. The ligule, found at the base of the leaf blade where it joins the sheath, is long and membranous. Flowering occurs from May to mid -June. The inflorescences are 3-16 inches long and initially purple tinged, with lax branches. As the seeds ripen, the inflorescences turn a tawny beige color and the branches close up against the main axis. The shiny seeds rain out of the inflorescences when disturbed after ripening. Seeds disperse on water, and are moved by humans and animals as well. The plants are clonal, spreading aggressively by rhizomes. Reed canary grass is adaptable in its cultural requirements, growing in dry upland soils and part shade as well as the moist to wet soils in full sun where it does best. Reed canary grass management should only be tackled if there are adequate resources for both adequate initial treatment as well as ongoing follow-up treatment. It is not reasonable to attempt to control a discrete area of reed canary grass within a larger system invaded by the grass, as there will continue to be inputs of seed and perhaps even invasion by rhizomes. Chemical A preferred method to control dense stands of reed canary grass is to broadcast treat it with glyphosate in early to mid -fall while the cool season plants are still actively growing and the chemical will be translocated to the plants roots and rhizomes. Glyphosate formulated for use over water should be used for reed canary grass control where it occurs in wetlands. In upland areas, glyphosate or a grass specific herbicide such as fluazifop-p-butyl can be used. When treating dense clones of reed canary grass, there is little chance of overspray contacting desirable species. However care should be taken to avoid overspray when treating smaller patches of reed canary grass occurring within a remnant or restored native plant community. Where feasible, mowing prior to herbicide treatment can facilitate application. Mow prior to seed production or in late summer for a fall foliar herbicide treatment. If the population is especially dense, one herbicide treatment is not likely to be enough for complete control. Mechanical In theory, intensive grazing, mowing or haying could diminish the resources of this robust perennial grass, but in practice that is difficult to achieve. Reed canary grass is typically found in environments that are too wet to mow as needed. In addition, this method will not eliminate reed canary grass. More likely, it will merely set reed canary grass back temporarily allowing some other species to occupy the space. But if ongoing maintenance does not occur, reed canary grass will recover and dominate the plant community again. Mowing can be used to facilitate herbicide treatment on invaded areas that are accessible by equipment. Mow ahead of herbicide treatment, allowing adequate time for reed canary grass to grow back. Prescribed fire can be used to remove thatch and prepare a previously treated area for follow-up treatment. Mowing can be used in lieu of a prescribed fire to remove the dead canopy of previously treated reed canary grass. Mowing, of course may be limited by access on wet sites. Long-term Management Monitoring and follow-up treatment will be necessary to obtain control. The seed bank will germinate once the canopy is removed and will require follow-up management. It is not advised to begin control