Looking out the window of my home in downtown Raleigh, I notice at least five invasive species creeping into my yard. Invaders that have found their way from lands far away and serve as a constant reminder of one of the leading global threats to biodiversity.
We find evidence of these pests throughout North Carolina. Whether accidental or intentional, invasive species are moved from their native habitat and establish in a new environment. Not all introduced species are invasive, however, and only when they cause damage to the new environment are they considered invasive. Those damages to native ecosystems can include predation on native plants and animals, competition with similar species, and introduction of disease. Impacts have been estimated to cost the United States more than $100 billion each year.
Within North Carolina there are hundreds of invasive species, including plants, animals, insects and microorganisms. Vines like Japanese honeysuckle and kudzu wind around trees stealing nutrients needed for growth. Fast-growing trees such as tree of heaven (ailanthus) and mimosa out-compete native trees for light, space and nutrients. Imported red fire ants, in addition to their painful stings, cause millions of dollars of damage to soybean crops. And off our coast, lionfish consume dozens of native species.
Any invasive species becomes successful through a variety of characteristics that make them more competitive in the new environment. These characteristics can include the ability to live in multiple habitats, novel methods for nutrient acquisition and their introduction to an area with similar environmental conditions as their home range. Evidence also shows that a sustained relationship with beneficial microorganisms can also confer invasive success.
In the Genomics and Microbiology Lab at the N.C. Museum of Natural Sciences, I am studying interactions between invasive species and their associated beneficial micro-organisms. My study looks at micro-organisms that grow around the roots of invasive weeds. Plants rely on their root micro-organisms for disease protection, water and nutrient uptake and growth promotion. By growing dandelions and other weeds in diverse soils collected throughout the state, I am interested in characterizing the bacteria and fungi that become more abundant in the presence of those plants. To this end, we can understand and learn from their success.
To contribute to slowing the spread of invasive species, you can start at home. Keep your yard local by only planting native plants, learning to identify invasive organisms, and becoming proactive in removing them from your property.
Julia Stevens is a postdoctoral research associate in the N.C. Museum of Natural Sciences’ Genomics and Microbiology Lab.