Monitoring Over 22 Years Documents Invasion of Rare Riverscour Plant Community on the Delaware River

A rare riverscour community along the Delaware River's New Jersey shoreline that supports numerous state-listed plant species was monitored three times between 1998 and 2020, revealing significant trends in richness abundance. Cover of nonnative invasive increased annually by 3.8% 3.7%, respectively, while 1.1% 1.3%. native stable; however, declined 0.42%. trees shrubs significantly nearly 6% annually, graminoid cover 1.5% herbaceous showed no trend. Shifts species' importance values documented establishment spread several shrub species, as well extensive reed canarygrass (Phalaris arundinacea). Native grasses sedges characteristic community, over half 147 identified, value sampling period. Future declines winter ice scour due to projected warmer, shorter winters underscore managing woody plants at this site. Reed also pose a challenge management preservation community.