Removing alien invaders
By Rob Smith / ecoRI News staff
It’s one of the bills under consideration this month as the
General Assembly’s annual session gets underway.
Members of the House Environment and Natural
Resources Committee heard legislation (H7071) introduced by Rep. Jennifer Boylan, D-Barrington,
that bans a list of nonnative invasive plants from being imported, sold, or
distributed in Rhode Island.
“We’re only one of four states without a prohibited plant
sale list,” Boylan told the committee. “We’re the only state in New England
without such a list.”
Invasive plant species are a growing problem in Rhode Island. A plant is considered
invasive if it was introduced into a region it’s not known to be native, can
reproduce and spread without human effort, and actively causes harm to native
species.
Invasives, whether on land or in waterbodies, typically
grow much faster than their native counterparts and crowd out natives. Unlike
native species, which have native predators, invasives typically have nothing
to keep them from spreading.
These invaders also have knock-on effects toward animals and
insects. Native milkweed plants are the primary food source for monarch
butterflies in the Northeast, but black swallow-wort, an invasive species, can
be mistaken by the insects as milkweed. Butterfly larvae can’t mature due to a
toxin on the swallow-wort, preventing them from becoming fully grown monarchs.
Rhode Island already has a statewide ban on aquatic invasive plants, but species such as water chestnuts typically aren’t clamored to be sold at local nurseries and plant shops. Like with aquatic plants, the Department of Environmental Management would be required to maintain a list of prohibited invasive land-based plant life.
Would banning them work? While some in the committee
supported the legislation, that doesn’t mean they believe it will have the
force of law.
“Sometimes we pass legislation and it doesn’t really get
enacted, that really concerns me,” Rep. Lauren Carson, D-Newport, said. “I
support this, it makes sense, but how do we really make change here?”
Supporters of the legislation said a lack of clear
enforcement wasn’t a reason to not pass legislation.
“I don’t think it’s going to be easy to enforce, but
enforcement is sometimes a spectrum,” said Jed Thorp, director of advocacy at
Save The Bay, testifying Jan. 22 in support of the ban list. “On one end
something as simple as sending a letter once a year can have a big impact, and
at the other end sending out an inspector in response to every complaint or
phone call you get and plenty of things in between.”
“If we’re doing this for maximum effectiveness on the
ground, we would fund a small PSA program and probably fund a half FTE for
random spot inspections and the word would get out,” said Rep. Jason Knight,
D-Warren. “With that, the word would get out.”
DEM in its written testimony noted its inspectors are
already stretched thin without further adding to their duties.
Other environmental groups in support of the ban include the
Rhode Island Land Trust Council, the Audubon Society of Rhode Island, and the
New England chapter of Backcountry Hunters and Anglers.
Similar legislation has been introduced in past years.
A 2019 version introduced in the Senate by then-Sen.
Erin Lynch Prata passed the chamber with a 36-1 vote, but died in the House
later that session.
The enforcement question lies at the heart of why countries
and states have such difficulty controlling the spread of invasive plants. It’s
difficult to find nurseries that stock mostly native plant species, and the
people buying the plants either don’t know enough or care about a plant beyond
how it will look in their yard.
Japanese barberry is one such plant. Brought to the
United States from eastern Asia in the 19th century, it’s an ornamental still
used in landscaping because of its autumn coloring and resistance to deer. But
it quickly invades woodlands and meadows, and chokes out native species.
What would that mean for Rhode Islanders? More ticks.
Japanese barberry is linked with a higher prevalence of deer ticks — about 12
times more — than areas without the invasive plant, thanks to its dense foliage
retaining higher humidity, providing a more favorable nesting area for ticks.
H7071 was held for further study.