Marching North - Range-shifting Invasive Plants
Many beloved garden species brought to North America from elsewhere have proven themselves invasive further south in the Mid-Atlantic states. These include romantic wisteria (Wisteria sinensis, Wisteria floribunda), reminiscent of old-fashioned gardens, fragrant butterfly bush (Buddleja davidii), and many common groundcovers, including vinca. With climate change, research anticipates these species will take up residence in New England, if they haven't already, posing new threats to our ecosystem.
While this new threat is daunting, range-shifting invasive plants also create a rare opportunity for proactive invasive plant management. The identities of problematic invasive plants in the United States are already known, and tools such as the Invasive Range Expanders Listing Tool (https://www.eddmaps.org/rangeshiftlisting) can project which species may soon arrive. (Coville, et. al., 2021)
A 2021 article published in Invasive Plant Science and Management ( https://par.nsf.gov/servlets/purl/10294548 ) examines the issue of northward marching invasives as the New England climate warms. www.cambridge.org/inp
By examining which plants are most likely to have major negative ecological impacts in New England, the authors hope to promote early detection and prevention. This article creates a watch list of twenty-two invasive plants that could threaten New England open spaces, to guide environmental planners. Many of these invasives also can impact agriculture economically, and unfortunately, most are still available for purchase at ornamental plant retailers or online.
The authors recommend that New England states proactively include these 22 plant species in future weed risk assessments. This strategy would prohibit the deliberate sale and planting of high-risk species as ornamentals and/or seed imports.
Some of these northward roaming invasives have already reached Massachusetts and are threatening enough to have made the Massachusetts Prohibited Plant list.
Porcelain Berry (Ampelopsis glandulosa): Neon blue or pink berries and fancy, deeply lobed leaves are the hallmark of this vine, found most frequently in the Arlington Town gardens, but spreading elsewhere - https://www.invasive.org/browse/subinfo.cfm?sub=78266
Chinese Wisteria (Wisteria sinensis): Who doesn't love draping wisteria blooms? But this invasive found on the bike path near the Bow/Frazer St. entrances climbs up trees, stretches in long, above-ground runners across the landscape to re-root, and puts down very deep roots nearly impossible to dig out. It is listed as invasive across mid-Atlantic and Appalachian states as far north as Rhode Island. https://www.invasive.org/browse/subinfo.cfm?sub=3083
Others have not yet reached invasive status in Massachusetts. But because they are invasive further south, early monitoring and control can help prevent the damage these plants inflict on ecosystems. We can do our part by declining to buy and plant these in our yards and gardens. A sampling:
Vinca (Vinca major): This very familiar ground cover is listed as invasive in Rhode Island, but is commonly sold in Massachusetts nurseries. Landscapers love this as their go-to solution for slopes. Vinca has been around a long time. Introduced from Europe in the 1700's, it is commonly found around old homesites. From these sites it has spread in dense mats into both open and dense woodlands. https://www.invasive.org/browse/subinfo.cfm?sub=4528
Paper mulberry (Broussonetia papyrifer): While it's only officially invasive in the Pennsylvania, New Jersey, Maryland region, it is creeping northward. Paper mulberry has been spotted in southern Rhode Island, and Essex county, MA - https://www.invasiveplantatlas.org/subject.html?sub=5208
Crimson Fountain Grass (Cenchrus setaceu): This ornamental grass, found in Virginia and Maryland, has not yet been reported in New England. https://www.invasiveplantatlas.org/subject.html?sub=6165
See the full list of 22 invasives to be monitored by following the article link below.
Citations: Coville W, Griffin BJ, and Bradley BA (2021). Identifying high-impact invasive plants likely to shift into northern New England with climate change. Invasive Plant Sci. Manag. doi: 10.1017/inp.2021.10 - https://par.nsf.gov/servlets/purl/10294548
