Monday, November 01, 2010

Invasive species are ubiquitous


    Invasive species are ubiquitous. They are chewing and chomping, growing and spreading their way through our forests, parks, landscapes, gardens and homes. They are directly altering the ecological systems in which we live while at the same time reflecting the activities of human life. In a very real sense they are evolving with mankind, and together we are coevolving with them. Our plowing, shopping, paving and voiding activities pressure the environment around us weakening the existing interactions of the existing ecosystems. In other words our regular chronic disturbance of the natural word not only provides a platform for new species to enter, but lessens the existing ecosystems ability to respond. The continuous activity, the unrelenting disturbance, lowers the ecosystems resiliency. At some point the impact of new species may cause the original system's overall patterns to shift into a novel or new set of patterns with a corresponding set of unexpected or unintended consequences


    The brown marmorated stink bug, Halyomorpha halys, is today's example of a rapidly spreading non indigenous species. Seemingly harmless except for the acute discomfort it brings to home owners, the lack of a comprehensive early detection and rapid response plan allowed the new species to get a firm foothold in the Mid-Atlantic and to naturalize in its new home so to speak. Even though we knew full well that, "[i]n its native range, it feeds on a wide variety of host plants. Fruits attacked include apples, peaches, figs, mulberries, citrus fruits and persimmons. This true bug has also been reported on many ornamental plants, weeds, soybeans and beans for human consumption. Feeding on tree fruits such as apple results in a characteristic distortion referred to as "cat facing," that renders the fruit unmarketable as a fresh product", we had no mechanism in place to deal with it early. [Steve Jacobs, Sr. Extension Associate

University of Pennsylvania]
     The invasive stink bug has many traits that will allow it to comfortably integrate, or perhaps I should say, insinuate, itself into our lives and landscapes. Maryland's Home & Garden Center repots that the stink bug is a strong flier and will quickly "drop" downward when disturbed, emit a strong, unpleasant odor when threatened or crushed. (the smell goes away quickly), are more sluggish on cool, overcast days, tend to congregate late summer/fall on warm, elevated surfaces. In addition, pesticides are generally ineffective and not recommended for controlling this pest inside or outside your home, according to the web site information page.
     As with most invasive species, by the time we get annoyed enough to thyink about doing something, the cost effective window is way past. The stink bugs are now moving out from our homes and gardens and attacking agricultural crops like corn and apples. And we shall surely pay the price in reduced yields of some of our favorite fruits and foods (like my peppers and tomatoes). We need to be changing how people think about the environment. We need to find away to make clear the interactions between our human activities and the patterns of nature upon which we depend.

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