I just attended an Illinois First Detector workshop that addressed several invasive pests, insects and diseases, and even certain kinds of wildlife. Some made their way into Illinois, some just over the state line, and others are in other states that grow food crops we eventually eat. The First Detector Program trains participants to look for the early signs of these invasive plants and pests, and report them.
One animal example that really stood out was feral pigs. While we do not have them around here, they have become a problem in other parts of our country. Feral pigs are vectors of at least 10 different diseases that are harmful to us, such as E. coli, trichinosis and rabies. These feral pigs were ultimately blamed for contaminating acres of spinach, which was then shipped into several states with E.coli.
Closer to home, one of the invasive plants we deal with is in the carrot family. You may have been hearing of reports of severe dermatitis. The culprits are wild parsnip, giant hogweed and poison hemlock. Both wild parsnip and giant hogweed will cause severe blistering when the sap is on the skin in the presence of sunlight. This is called phytophotodermatitis. Extreme care is required if handling either one of these. There is not a safe part of poison hemlock either, as it contains four different compounds that are poisonous to humans.
Another very interesting part of this presentation is the "uptick" (pun intended) in the presence of ticks, and the six diseases they carry. Common ones we know of include Lyme disease and Rocky Mountain spotted fever. Where you have an invasive plant species that has colonized an area, the microenvironment changes with increases in humidity, allowing for higher tick survival rates and an easier source of potential blood donors. One example was an 18 percent increase in tick presence where honeysuckle had established over a native uninvaded area.
I was surprised to learn that one of the more common nuisance plants in the landscape, Tree of Heaven, can impart some potentially serious health issues. Contact dermatitis happens when being exposed to the sap. Reactions vary from a simple rash to more severe, such as myocarditis, intestinal pain, chest pain and shortness of breath. These kinds of symptoms are not unlike those of a heart attack.
Invasive species have been affecting human health for a long time, yet we are just now quantifying how much. These examples are very real and we should avoid coming into contact with any of these carrot family invasive plants and avoid any prolonged exposure to Tree of Heaven. Removing invasive species can dramatically reduce insect populations that spread human disease. Besides managing invasive plants to preserve our native plant species, we now have another great reason to be concerned with invasive plants. Learn more at http://wwx.inhs.illinois.edu/research/caps/first-detector/