Stopping the Space Invaders

Krista Connor

The new Delaware Native Species Commission is targeting invasive plants in order to reverse the state’s dangerously high native plant decline, a threat that starts in our own backyards

A good portion of the greenery Delawareans might admire along the highway or bring home and plant in neat rows outside the front window doesn’t, well, actually belong here. And it’s causing major problems by pushing local plant species to extinction, which has a series of consequences—including the disappearance of local wildlife.

But, according to environmental expert and State Sen. Stephanie Hansen, the threat posed by invasive species can be reversed and biodiversity restored.

Last year, Hansen, who assumed office in February 2017, piloted The Ecological Extinction Task Force, made up of a statewide team of researchers and advocates from various backgrounds, including government, educational and environmental organizations, DNREC, the University of Delaware and the Delaware Nature Society, among others.

During the winter, the task force released a report warning that the proliferation of invasive plant species paired with a rapid decline of wildlands are causing severe damage to Delaware’s ecosystem. One study shows that 79 percent of plants in Delaware’s suburbs are non-native species. Another reveals that three in every four plants that nurseries introduce to the area are non-native or invasive.

With Delaware being home to more than 800 species of wildlife and 100 habitats, its natural diversity is of obvious importance, according to the Wildlife Species Conservation & Research Program.

So, the task force presented more than 80 recommendations to reverse the problem in a statewide call to action to government officials, businesses and the public. The aim is to improve land management practices, safeguard local ecosystems, and reverse the trajectory that has brought local species near or past the point of extinction.

“You can reverse the trend,” says Hansen, of Middletown. “In some cases, it’s not so hard to do. It’s about bringing it to people’s attention.”

Maintaining momentum was a major concern, so one task force recommendation was for the state to pass new legislation putting into place a commission, Delaware Native Species Commission (DNSC), to implement the 80-plus recommendations. The bill establishing the commission was signed into law by Gov. John Carney on June 7.

The commission will run for at least 10 years, and can be extended further if the General Assembly finds it necessary. Each year the commission must report back with its progress.

Monarch butterflies on blue mistflower. Photo Lori Athey

The Bad & the Good News

Hansen, who has a professional background in geology, earth science and environmental law, was inspired to launch the task force after hearing a lecture by Dr. Douglas Tallamy, a UD professor and leading scholar on local extinction.

Tallamy’s research shows that 90 percent of herbivorous insects eat specific vegetation from their native habitat. The loss of their food supply has resulted in food shortages for larger species, including birds, reptiles and fish. Coupled with the loss of woodlands and animal habitats around the state, this has caused rapid decline or disappearance of the following: 20 percent of local fish species, 31 percent of local reptile and amphibian species, 40 percent of local plant species and 41 percent of local bird species that rely on forest cover.

Those numbers staggered Hansen and spurred her to action.

It doesn’t help that among Delaware’s more than 1,500 species of native plants, 25 percent are rare. How many will disappear if Hansen and the DNSC don’t continue their work?

“They’re all on a slow death march,” says Hansen. “The idea behind this is to turn the ship around.”

The report’s recommendations include calls for a number of corrective steps, including a phased-in ban on the sale of invasive species.

Positive change is afoot, starting with New Castle County parks. In May, task force member Tracy Surles, who also serves as Special Services general manager for New Castle County, convinced County Executive Matt Meyer to put in place an executive order in which only native plant species will be planted in New Castle County’s parks—a big step, since there are 247 of them.

More good news comes from the Village of Fox Meadow, an active adult community in Newark. Task force members, with the help of grants, have helped residents turn their open space into a native plant area and meadow. As far as Hansen knows, this is the first example of a community coalition, and she hopes more will follow.

Up next, Hansen will meet with DelDOT, which is one of the largest landowners in the state. She hopes to influence changes regarding native species, especially along transportation corridors.

And local company Borsello Landscaping is in the lead among lawn care competitors by offering native plant expertise. Owner Mike Borsello says the company has been working with native plants for more than 20 years. He says that native plants are typically more deer resistant and require less care than non-native. “When a client hears [that], and that they are better for the environment, it’s just an easy conversation.”

On a national level, one-third of all wildlife species are at risk of extinction, according to the National Wildlife Association. The NWA reports that more than 150 species in the U.S. have gone extinct. It comes as no surprise that there’s a direct link between that and invasive plant species.

“They remove a food source from the bottom half of our food chain, and displace our native plants, which are the food source for that bottom half,” says Hansen.

So, What Can We Do?

There are dozens of regional councils and task forces, but as of now no national coalition. Hansen says that would be extremely effective. But instead of looking to the government for the solution, Hansen urges individuals to take action: “People need to own this on a personal level.”

Native plants, like the buttonbush, can support various species of insects, like the tiger swallowtail butterfly and bumblebees. Photo Lori Athey

She suggests that when planting, avoid common invasive species like burning bush, English ivy, Asian varieties of honeysuckle and stiltgrass, Norway maples, and rapidly spreading weeds. The weeds drive out native plants and dominate surroundings. None of these species contribute to the local food supply and are killing off plants that do, says Hansen.

The Trojan horse of invasive species is the Bradford pear tree. Introduced in the U.S. by the Department of Agriculture in the 1950s because they were “pretty when they bloomed,” says Hansen, they’ve spread like an epidemic from housing developments and shopping centers where they were planted, and have now displaced many of the state’s native oaks, pines, maples and elms along transportation corridors and elsewhere.

The Bradford pear doesn’t support Delaware’s native insect population, which then affects birds and amphibians. Tallamy’s research shows that native oaks support more than 400 insect species, while only four types of insects are found on the Bradford pear.

The mission now is to educate Delawareans—especially private landowners—about the problem and create incentives for them to be part of the solution by buying and planting native species.

“You have to do it in a way that brings people along by education—it’s difficult to do this with a hammer,” says Hansen. “This isn’t something we were turning around saying, ‘Call your state representatives and senators.’ This is about what are you planting in your front yard?”

She urges residents to research native plants and educate themselves through resources like Delaware Livable Lawns (delawarelivablelawns.org).

According to reports from DNREC, University of Delaware and Mt. Cuba Center, native plants include: flowering dogwood, black-eyed Susan, butterfly milkweed, orange coneflower, mountain laurel, oakleaf hydrangea, silverbell, golden Alexander, arrowwood and varieties of ferns and trillium. Extensive lists and resources are available online, and native plants can be found through Delaware Native Plant Society (delawarenativeplants.org) and at nurseries through Delaware Nursery & Landscape Association at dnlaonline.org. Borsello recommends Gateway Garden Center in Hockessin.

“How are you supporting our ecosystem?” says Hansen. “Because we can bring this back, but it’s going to be brought back on an individual, person-by-person, property-by-property basis.”

Go to mtcubacenter.org, delawarenaturesociety.org, ceoe.udel.edu and dnrec.delaware.gov to learn more about native plants and where to find them.

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