BETHEL, Vt. - Last year's hurricanes and flooding not only engulfed homes and carried away roads and bridges in hard-hit areas of the country, they also dispersed aggressive, invasive plant and animal species.
The overflowing Missouri and Mississippi rivers last year launched Asian carp into lakes and oxbows where the fish has not been seen before, from Louisiana to the Iowa Great Lakes. Flooding also increased the presence along the Missouri River of purple loosestrife, a plant that suppresses native plants and alters wetlands.
In Vermont, the floodwaters from Tropical Storm Irene and work afterward to dredge rivers and remove debris spread fragments of Japanese knotweed. The perennial was originally imported from Asia as an ornamental, but now threatens to take over flood plains wiped clean by the August storm.
The U.S. Army Corps of Engineers will spend $135 million on controlling invasive aquatic plants this fiscal year.