3 minute read
Invasives for Sale
By Evelyn M. Beaury, Madeline Patrick, and Bethany A. Bradley
The sale of ornamental nonnative plants is a primary pathway of invasive plant introduction into the United States. This study aimed to assess how effective voluntary and regulatory efforts have been at reducing the spread of invasive plants through horticulture. To do so, we compiled a list of 1,285 plant species listed as invasive, including state prohibited plant lists, the federal noxious weed list, and unregulated species listed by the Invasive Plant Atlas.
Using standardized internet searches, we found that 61% of these invasive plants are still on the market as ornamentals somewhere in the lower-48 United States, many of which can be bought and sold online through websites like Amazon, eBay, and Etsy. Regulated plants were sold less often than non-regulated plants (Table 1), but there were many instances in which regulated plants were sold in states despite their regulations.
Massachusetts prohibits the sale of 135 plants; 65 are commercially available somewhere in the U.S., but only three are for sale within the state of Massachusetts. Regulators have already followed up with local nurseries to reduce the reoccurrence in Massachusetts, but due to inconsistencies in state prohibited plant lists, we often found that Massachusetts prohibited plants were sold legally in neighboring states, leading to high risk of invasion within the region.
We therefore urge everyone to increase their awareness, not only of the Massachusetts prohibited plant list, but also of prohibited plants elsewhere in New England and in the Mid-Atlantic regions (more information can be found on the National Plant Board website). As the climate changes, many ornamental invasives from further south will find suitable habitat in New England. Preventing these species from damaging our native ecosystems requires a renewed focus
Table 1: Count and Percentage of Invasive Plants Available for Purchase as Ornamentals Within the Continental U.S.
This article was first printed in Frontiers in Ecology and the Environment, Vol. 19, isuue 10, pp. 550-556.
on reducing the spread of harmful nonnative plants through horticulture. For more information, see www.risccnetwork. org/management-challenges.
The Massachusetts Prohibited Plant List provides a list of plants for which importation and propagation is currently prohibited within the state of Massachusetts. The original list of prohibited plants went into effect January 1, 2006. Certain species were subject to a phase-out period that expired on January 1, 2009. Three new species were added in February 2017. Currently, the sale, trade, purchase, distribution, and related activities for the species below, including all cultivars, varieties, and hybrids, are not allowed. Visit the list at www.mass.gov/ massachusetts-prohibited-plant-list. Evelyn Beaury (Eve) is a Ph.D. candidate in the Organismic and Evolutionary Biology program UMass Amherst. She is broadly interested in invasive species, plant community ecology, and the impacts of global change. Her current projects are focused on understanding variation in biotic resistance across ecosystems of the U.S. and the role of the plant nursery industry in distributing invasive species. In addition to research, Eve is passionate about science communication and outreach and is a research scientist in the NE Regional Invasive Species and Climate Change Management Network.
Madeline Patrick is an associate analyst at National Grid, University of Massachusetts Boston.
Bethany Bradley is a professor of biogeography and spatial ecology in the Department of Environmental Conservation at UMass Amherst. She The number of vendors offering each species for sale versus the number of states in which the species was regulated. Asterisks indicate species pictured on the right. Top: panicled hydrangea (Hydrangea paniculata; photo by F. Vincentz); middle: Japanese barberry (Berberis thunbergii; photo by E. Beaury); bottom: yellow iris (Iris pseudacorus; photo by J. Billinger).
is interested in how the geographical locations of species across landscapes and regions can inform ecological understanding of species distributions, invasion risk assessments, and conservation planning. Her research has a strong focus on terrestrial plant invasions, with a goal of understanding how invasion risk varies spatially in the context of anthropogenic disturbance and climate change.
Editor’s note: MNLA is represented on the Massachusetts Invasive Plant Advisory Group (M.I.P.A.G.) by David Anderson, Mayer Tree Service; Pat Bigelow, MCH, Bigelow Nurseries; Wayne Mezitt, MCH, Weston Nurseries; David Vetelino, MCH, Vetelino Landscape Inc.
