Invasive species issues can be confusing, obtuse, complicated, ill-defined and contentious. And invasive species problems and their solutions become vaguer the closer one looks. Can a native species be invasive, and who defines this invasive quality? Are all invasive species bad? Are pet cats that become adapted to the parks and natural areas around our homes and fields invasive species? If an invasive species has a economic or social benefit is it still an invasive species? How long does an exotic alien have to be in the country before it becomes naturalized? Sometimes it is helpful to limit the scope of inquiry so that the imponderables do not overwhelm the questioner.
In the case of the hornworm, the end game is "... a brown moth that rarely shows up on the top ten wish-I-had-in-the-garden list. The adult moth, sometimes referred to as a "sphinx", "hawk", or "hummingbird" moth, is a large, heavy-bodied moth with narrow front wings. The moth is a mottled gray-brown color with yellow spots on the sides of the abdomen and a wing spread of 4 to 5 inches. The hind-wings have alternating light and dark bands." Relegated to second class oblivion and adult obscurity without the protection of charismatic status, the hornworm lacks a fan club clamoring for its immediate local victory. The tomato hornworm caterpillar is labelled invasive because it comes into this little patch of Russian pickling heaven and negatively impacts, or drastically disturbs the carefully planned interconnections between selected plants and human dinner. The caterpillar is a classic, traditional example of an invasive species from a gardener’s point of view.
In the world of invasive species all of us are stakeholders and all of us have a duty to be part of the conversation bringing the “rightness” of our positions to the debate. In the end science cannot provide policy and value answers but rather it can give us the tools for identifying the limits of our knowledge. It is up to each of us to address the value system that best supports the world we want to live in and how much we want our children to pay for our actions and our dreams.