Aquatic Plant Research > Invasives > Invasives in Trade
Aquatic Plant Research
Invasives in Trade
One vector of invasive species introduction can be through the aquatic plant trade. Assessing the current availability of prohibited and restricted invasive species in the trade is an important step to guide education and outreach to prevent future introductions.
DNR Science Services conducted a social survey of live aquatic plant retailers in Wisconsin before and after educating retailers about Wisconsin’s invasive species regulations. The goal of the survey was to learn if education on invasives species regulations could influence retailers' self-reported behavior and beliefs about invasive species. Researchers also wanted to know how retailers wished to receive information about invasive species, and what barriers might keep a retailer from complying with invasive species regulations. Reported compliance and use of best management practices increased slightly following education, and researchers found combining an in-person visit with mailed educational materials to be more effective than just the mailer at achieving compliance with regulations.
Egeria densa is a widely-available invasive plant used in both aquaria and water gardens. It is regulated as prohibited in WI, but fortunately, there are several closely related plants also available in the live plant trade that can be used as alternatives. This document was created to help distinguish between the regulated plant, and two possible alternatives. These documents are useful for stores working to bring their stock into compliance, for aquarists wishing to avoid purchasing regulated plants, and for teachers demonstrating cell properties with live plants.
Concerned citizens from around the state reported that aquatic invasive plants were readily available in pet stores and garden stores despite regulations prohibiting the sale of certain species that had been in effect since 2009. DNR Science Services investigated whether education and outreach increased the rate of NR40 compliance by live aquatic plant retailers. Plants available for sale were surveyed in stores before and after one of two education programs. Stores were either sent a mailing about invasive species regulations or sent a mailing and visited by the DNR invasive species educator to talk about regulations, plant identification, and best management practices. Education did improve compliance with regulations (from 51% noncompliance by retailers down to 26% noncompliance), and visiting stores was more effective at improving compliance than the mailer.
DNR Science Services assisted in creating a reference sheet for retailers and gardeners that shows the names of plants regulated under NR 40 and all of the synonyms the plants are sold under in the live plant trade. Each listed plant has many alternate names. This list is essential for stores working to bring their stock into compliance, or for gardeners wishing to avoid purchasing regulated plants. In addition to the reference list, a fact sheet was also created to address just the most commonly-encountered plants and their synonyms.
Concerned citizens from around the state reported that aquatic invasive plants were readily available in pet stores and garden stores despite regulations prohibiting the sale of certain species that had been in effect since 2009. In addition, populations of NR40 prohibited plants continued to be found in ponds and water gardens. DNR Science Services wanted to learn 1) how prevalent the sales of regulated invasive species were across Wisconsin; 2) if education and outreach with live plant retailers could increase the rate of NR 40 compliance; 3) whether invasives were more likely on the landscape nearby retail outlets selling invasives; and 4) whether retailers' self-reported behavior and beliefs about invasive species changed following education. Researchers found that illegal species were available for sale by 51% of retailers. Compliance and adherence to best management practices improved following education (availability of illegal species down to 26% of retailers), with one-on-one educational visits to stores more effective than mailings about the regulations. Researchers found that invasives in ponds are more common in the live trade than plants not found in ponds, and that some species are more likely in ponds closer to stores (notably, purple loosestrife).
Concerned citizens from around the state reported that aquatic invasive plants were readily available in pet stores and garden stores despite regulations prohibiting the sale of certain species that had been in effect since 2009. In addition, populations of prohibited plants continued to be found in ponds and water gardens. This study looked at the relationship between retail sources of invasive plants and invasive plants on the landscape. Researchers found that the most common invasives in ponds are also the most common in the live plant trade, and that ponds with purple loosestrife are more likely closer to stores selling aquatics. Researchers also found that when considered together, regulated species in ponds are closer to stores selling regulated species. This work shows that there is a link between availability of invasive species and presence in ponds.
DNR invasive species education staff created an outreach document targeted at best management practices for pond owners. With technical assistance from DNR Science Services, this brochure was then sent to 15,000 Wisconsin landowners with ponds on their property to highlight responsible pond ownership and increase awareness of invasive species regulations. Pond owners aware of the NR40 regulations are less likely to purchase illegal plants from stores selling them, and more likely to report an invasive species, helping in both prevention and early detection of invasive species. This is the first outreach effort of its kind in the state.