By: centraljersey.com
Mother Nature can be a capricious mistress. In recent years, we’ve seen an unexplained devastation of bat and bee populations. We’ve also witnessed the successful return of the eastern bluebird after years of decline due to competition from non-native birds. But a new blight attacking the non-native multiflora rose has the potential to wipe out this aggressive and invasive rose, and, in the process, help our native plants.
Multiflora rose (rosa multiflora) is one of the most prominent invasive plants in this state we’re in. It was imported from Japan in 1866 as a rootstock for ornamental roses, and was later planted for erosion control, highway crash barriers, bird habitat and hedgerows. As a classic "exotic invasive," however, it wasn’t long before the rose grew densely enough to crowd out native species all over the U.S. countryside.
Invasive plants are one of the biggest threats to the Garden State’s biodiversity. They easily out-compete native plants and take advantage of our state of affairs: forests fragmented by sprawl development and weakened by over-browsing from too many deer. Deer eat up the native forest understory, clearing the way for invasives, which they don’t eat.
According to the 2004 state Department of Environmental Protection report "An Overview of Nonindigenous Plant Species in New Jersey," we host around 1,300 species of nonindigenous plants, enough to put us among the top five states with the most invasive species. In addition to multiflora rose, some of New Jersey’s top invaders are purple loosestrife (lythrum salicaria), common reed (phragmites australis), autumn olive (elaeagnus umbellate) and Japanese stiltgrass.
Invasive species cause significant and sometimes irreversible damage and cost millions of dollars in economic losses. A 1999 Cornell University study pegged agricultural losses from lower crop yields and invasive control expenses in the United States at more than $30 billion per year.
Government agencies spend billions to control or eliminate invasives with very little to show for it, at least compared to the scope of the problem. But now, Mother Nature has come up with her own weapon against multiflora rose in the form of a virus called rose rosette disease. It is not surprising since our plants and animals are constantly evolving in relationship to one another. When one species becomes abundant, another often rises up to out-compete, attack or otherwise interact with an unexplained outcome.
In the case of multiflora rose, its attacking disease produces rapid elongation of new shoots, then development of "witches’ brooms" (clusters of small branches) with small, distorted leaves that may have a conspicuous red pigmentation. Infected rose plants often die within one to two years. Ironically, in some infected areas, land stewards are leaving the dead multiflora rose bushes in place because they now provide shelter for the young shoots of the native species they once choked out.
To learn more about rose rosette disease, consult the Virginia Cooperative Extension website at http://pubs.ext.vt.edu/450/450-620/450-620.html.
We can spend billions on eradicating various invasives, sometimes with the same result as using a slotted spoon to empty the ocean. It’s a reminder that, for all our human intelligence and creativity, we need Mother Nature’s help to address problems of our own making.
Michele Byers is executive director of the New Jersey Conservation Foundation. For more information, contact her at [email protected] or visit NJCF’s website at www.njconservation.org.
