Invasive Plants Are Still Being Sold. We Can Fix This.
I attended sessions from the Northeast Regional Invasive Species and Climate Change (RISCC) Symposium, and one message came through clearly:
We are not lacking knowledge. We are lacking alignment between what we know and what we do.
Across North America, invasive species are accelerating under climate change. New plants are emerging, others are expanding northward, and ecosystems are being reshaped in real time.
The problem is not accidental
Dr. Bethany Bradley reminded us that roughly 60% of known invasive plants, like Japanese knotweed, were intentionally introduced as ornamentals (Lehan et al. 2013). That is not a historical footnote. It is an ongoing pathway.
Nicholas Stevenson, team lead for Invasive Plant Management with the U.S. National Park Service, flagged emerging threats for the Northeast like:
- Ficaria verna (lesser celandine)
- Iris pseudacorus (yellow flag iris)
- Rhodotypos scandens (jetbead)
- Clematis terniflora (sweet autumn virgin’s bower)
- Aralia elata (angelica tree)
Many of the ornamental plants named are available in nurseries across North America.
Our current regulatory systems are not built for prevention
Both in the United States and Canada, plant regulation remains fragmented across jurisdictions, inconsistent between regions, and reactive, acting only after significant harm is visible.
RISCC is developing a new regulatory comparison tool to make these gaps visible (www.riscctools.org/regulatory-visualization/). I am hoping to convince them to extend this tool into Canada, but in the meantime, I’ve posted provincial and territorial regulations on CCIPR.ca for comparison.
We don’t have a knowledge gap. We have an action gap.
Many organizations, like Master Gardeners, are working to educate the public. We prompt change with: “Don’t plant this.” “Report that.” “Remove this species.”
But as highlighted in work presented by Dr. Winslow Robinson, this approach runs into a well-known barrier: the information–action fallacy. People do not act simply because they are informed.
The Fogg Behavior Model makes this clear: action requires motivation + ability. Right now, we often provide the prompt to motivate action, but not the conditions that make action easy or likely.
Making action easier
Tools like the Climate-Smart Plant Selection Tool, being developed by Matt Fertakos and Thomas Nuhfer at the University of Massachusetts Amherst, may help bridge that gap. This tool helps gardeners select native and near-native plants suited to both present and future climate conditions.
Available at www.climatesmartplants.org/plant-selection/, this database will allow users to filter by growth habit, climate status, sun level, moisture, hardiness zone, bloom period, colour, pollinator value, showiness, soil type, wildlife services, and more. While it doesn’t yet extend to Canada, the team was open to building in that capability.
What needs to happen next
I hope you are feeling a bit more motivated to address the problem, and that you will join me in taking action to slow the spread of invasive plants.
Learn more. Join and follow RISCC https://www.risccnetwork.org
Northeast RISCC https://www.risccnetwork.org/northeast Research to Practice https://www.risccnetwork.org/research-to-practice
YouTube Making Invasive Species Management Easier To Do ~ Winslow Robinson