Plant Risk Evaluator Tool Helps Identify Potentially Problematic Plants
By Steve Elliott, Western IPM Center
The easiest pest to manage is the one that’s not there.
It’s true for any pest type – destructive insects, hungry rodents or fast-spreading weeds. No management technique is more effective or less costly than preventing that pest from becoming established in a new area to begin with.
That’s why prevention and avoidance are first two principles of integrated pest management’s “PAMS Approach,” with monitoring and suppression following behind.
It’s also the rationale behind the Plant Risk Evaluator Tool, an online database to evaluate the potential for ornamental and horticultural plants to become invasive weeds in different areas and environments.
“The tool relies on both climate suitability – where it grows well and whether that climate matches the area that you are interested in – and on plant characteristics, such as impact, reproductive strategies and dispersal,” explained Jutta Burger, the science program director at the California Invasive Plant Council. “It includes questions about a plant’s habits, like does it produce a lot of seed, does it disperse very easily, and what its invasive tendencies have been in other areas, especially areas that suit the climate of the area that you're looking at.”
For instance, a plant that thrives in cool, damp coastal conditions could easily be flagged as potentially invasive in the Pacific Northwest and Northern California but not a concern in Arizona or Utah.
The Plant Risk Evaluator, or PRE tool, was originally developed by the University of California, Davis and the University of Washington, with support from Sustainable Conservation. It’s now managed by PlantRight, a project designed to keep invasive plants out of horticulture. For the past several years the tool has been supported and updated by a team led by the California Invasive Plant Council, which is commonly known as Cal-IPC (and pronounced Cal Ipsy), and PlantRight.
With four consecutive years of competitive Western Integrated Pest Management Center funding, Cal-IPC and PlantRight put together a multi-state work group to expand use of the tool into new Western states, moved the online tool to a new and more stable web system that will have a publicly accessible database, trained new users to evaluate plants and helped oversee the evaluation and addition of several dozen new species – mostly of horticultural origin – into PRE’s growing database of now nearly 600 species. Last year, supporting a North Central IPM Center program, Cal-IPC recruited public gardens in the West to a program that trains them to act as sentinels against invasive ornamental plants.
The Plant Risk Evaluator was originally designed for university and industry professionals and is used to encourage landscapers and garden centers not to stock and sell plants with invasive potential. (For a public-facing website about which potentially invasive plants to avoid and what to plant instead, visit PlantRight’s website at plantright.org.)
Cal-IPC’s latest effort is to enlist Master Gardeners throughout the West into the ongoing battle against invasive plants.
“We’ve started doing trainings for Master Gardeners throughout the state of California and hope to begin working with other states and extension programs to help them engage their Master Gardeners as well,” said Constance Taylor, a Cal-IPC conservation specialist. “Just providing Invasive Plant and Horticulture 101-type of information has been really useful: what invasive plants are, where they come from, how horticulture and landscaping can be involved in their spread, and how Master Gardeners can educate the public about invasive plants.”
Taylor said because Master Gardeners are often active and visible in their communities, they can be effective in educating and providing resources to others.
“People are generally receptive to not planting plants that are going to be a problem, if they have that knowledge,” Taylor said. “With some training, Master Gardeners can serve as ambassadors, get to know some of the weeds of concern in their areas and start looking for them and reporting them. That’s something extremely useful in invasive weed management.”