Natural history, distribution, and management of Lepidium latifolium (Brassicaceae) in New England.

摘要

Lepidium latifolium (perennial pepperweed) is an herbaceous perennial, native to Europe and western Asia, that is now well established at many locations in Massachusetts and Connecticut. This species is considered a major invasive species in the western United States and appears likely to become invasive in the east if left unchecked. We showed that the distribution is greater than previously documented in New England and that populations appear to be expanding. Individuals of the species can produce thousands of seeds and we found that these seeds are tolerant to many days of inundation by salt water so that dispersal by tidal and river currents is likely. In addition, populations can expand at least 2 m/yr from growth by rhizomes, and densities exceeded 50 shoots/m2 in some areas. We identified 17 species of plants that are likely impacted by the expanding populations and 23 families of arthropods associated with L. latifolium in some of these areas. In wetland habitats, repeated pulling of shoots to remove much of the rhizome was effective at stabilizing or eradicating whole, well-defined populations. This treatment was most effective if continued for two or more growing seasons..