Reeds run amok: A practical guide to managing phragmitesinvaded wetlands Christine B. Rohal, Keith Hambrecht, Chad Cranney, Karin M. Kettenring Introduction Phragmites australis (common reed or simply “phragmites”) is a tall-statured, highly productive wetland grass. In winter, phragmites goes dormant, leaving behind large amounts of dead plant material that is slow to break down (Figure 1). The combination of living and dead phragmites biomass creates a thicket of dense, often impenetrable, vegetation. There are both native and introduced subspecies of phragmites in North America. The non-native subspecies of phragmites (Phragmites australis subsp. australis), which originated in Eurasia, grows more aggressively than the native subspecies (Phragmites australis subsp. americanus).1 Non-native phragmites is currently predominant in Utah’s Great Salt Lake and Utah Lake wetlands, as well as many smaller wetlands, roadsides, and other disturbed areas.1 Native phragmites generally occurs in much lower densities and is distributed throughout the state, particularly in areas with minimal human disturbance.1
Figure 1. Phragmites in winter with last year’s inflorescences.
Why manage phragmites Phragmites grows in tall, dense stands that shade out native plants (Figure 2). It spreads rapidly, often displacing native plants and degrading critical habitat for shorebirds and waterfowl by reducing the availability of nesting, loafing, and foraging areas. Phragmites also consumes large amounts of water, adding pressure to already scarce water resources. Additionally, the accumulation of standing dead biomass can be a fire hazard. Phragmites makes large areas of wetlands inaccessible to both wildlife and humans.2,3
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