A minute of natural history
|Mile-a-minute overtaking trees.|
by Furryscaly via Flickr CC
|Approximate U.S. distribution as of July 2013. Source: Eddmaps.|
Mile-a-minute earned its name
|Mile-a-minute leaves and ocreae. |
by Leslie J. Mehrhoff
|Following annual die-back mile-a-minute |
leaves and stems continueto weigh down the
plants they have climbed & shade groundcover.
by L. J. Mehrhoff via Invasives.org
Fighting nonnative with nonnative: biological controlBiological control is a way of using an invasive species natural predator or disease, most often from the species’ indigenous region, to reduce the invasives’ proliferation and dominance. Finding a biological control agent that is truly host-specific to your target species takes a lot of research. Inadequate research into a control agent’s life history and ecology prior to release may have dire consequences, which are worse than the original cause for their introduction. A classic example of biological control gone awry is that of Cane Toads introduced to Australia in 1937. Thankfully, the science of introducing biological control agents has come a long way!
|Adult R. latipes are approx. 2mm long.|
by Amy Diercks, via Invasives.org
Colpetzer et al. published a study in Biological Control (2004) examining potential biological control agents for use on mile-a-minute. Results from their study supported the introduction of a small host-specific weevil from Asia, Rhinoncomimus latipes, which feeds on mile-a-minute roots as a larvae and foliage as an adult. In 2004, the U.S. Department of Agriculture approved the use of the weevil as a biological control agent. After several regional releases, the introduced weevils have successfully established populations throughout the Mid-Atlantic region.
Ongoing weevil releases, such as one recently conducted in Union County, New Jersey, help sustain and expand the current weevil populations. Led by state and county agriculture officials, the recent release of 2,000 weevils in Watchung Reservation, Union County’s largest park, is sure to reduce local mile-a-minute growth in the coming years.
Below is a video from a weevil release in New York City
Amy Diercks, Bugwood.org