A species is considered invasive when...
[more info coming soon...]
Are all invasive species introduced?
No! [more info coming soon...]
Why is Phragmites australis considered invasive?
Recently Phragmites has spread rapidly threatening biological diversity in many natural areas. Like most invasive species, Phragmites is displacing native vegetation with negative impacts on native flora and fauna. The extent of loss is difficult to measure due to the lack of long-term data. Ecological damage includes alteration of nutrient cycles and hydrologic regimes.
Although Phragmites rhizomes found in peat cores have been dated to over 3000 years ago, suggesting this species is native to North America, genetic analyses suggest that aggressive genotypes may have been introduced in more recent times. These genotypes may be responsible for the recent population explosion.