Invasive plant talk highlights ecosystem restoration, responsible planting

Southeast Alaska Watershed Coalition and Tlingit and Haida discuss prevention and management 

Invasive perennial sowthistle grow on a beach in Auke Bay on Sept. 28, 2026. (Ellie Ruel / Juneau Independent)

By Ellie Ruel

Juneau Independent

Despite the unseasonably dreary weather, the invasive species marking the first (unwanted) signs of spring were the topic of Friday’s Fireside Chat hosted at the Mendenhall Glacier Visitor Center. Presenters from the Southeast Alaska Watershed Coalition and the Central Council of the Tlingit and Haida Indian Tribes of Alaska laid out how prevention and containment can preserve ecosystems disrupted by human influence.

Invasive plants are non-native species introduced through human action that have the potential to cause ecological or economic damage. But the delineation of harmful versus nonharmful can get tricky at times, said Emily Reed, regional invasive plant coordinator for the Southeast Alaska Watershed Coalition. 

“There's a lot of ambiguity in these terms. So, native versus non-native, it can be hard to determine, especially if the plant has been somewhere for a long time, and then weighing benefits versus harm,”  Reed explained. “It's not a yes or no. There's a continuum.”

For example, she said, dandelions are non-native plants but mostly grow in disturbed areas and provide benefits for local pollinators and bear populations. Likewise, horsetails are native plants, but can easily take over large swaths of land, pushing out other species.

Determining how invasive a species will be falls to the Alaska Invasive Species Partnership, which consists of municipal, state, and federal agencies, tribal governments and citizens, and nonprofits. Plants are ranked on a scale from zero to 100 points based on a variety of factors.

“The ranking is based on four different areas: the impact, the biology of the plant, and how it disperses, its global distribution and establishment — if it's invasive somewhere that's similar to Alaska, there's a good chance they’'ll be invasive here — as well as how difficult it is to control,” Reed said.

She noted the score can be used to determine where funds for ecosystem restoration or invasive plant removal go, and scores above 60 receive more support for removal.

In Southeast Alaska, the plant with the highest score is Japanese knotweed, ranked at 87. It is considered to be one of the most invasive plants in the world. Japanese knotweed can spread easily since it reproduces through its rhizome, a horizontal underground portion of stem that stores starch and protein, and can propagate new roots and shoots. Since it only takes a tiny chunk of rhizome to generate a whole new plant, Reed said pulling it isn’t usually helpful, but herbicides can be effective. She’s also experimenting with cutting the stems back periodically to exhaust the knotweed’s energy reserves.

“It just is so good at establishing anywhere. It does a really, really good job at what it evolved to do, which is to spread and survive,” she said. “A tiny little rhizome fragment can be all it takes to start a new population.”

Reed said other concerns include European Mountain Ash, a common decorative tree with red berries that are highly attractive to birds; reed canarygrass, a species that was originally used to revegetate mining roads, but can disrupt stream ecology and hydrology; and orange hawkweed, a distinctively orange-red flower that lowers species diversity and forage value of grassy areas. 

She said people can help prevent the spread of invasives by checking for “hitchhiker” seeds and plant parts that stick to boots or dog fur,  not dumping yard waste on the side of the road, and checking that ornamental plants won’t pose a risk of invading the ecosystem. Last fall, the State of Alaska issued a quarantine on chokecherry trees due to their invasive nature and potential to give moose cyanide poisoning.

According to Reed, integrated plant management practices can help contain even the peskiest of invasive populations.

“It's basically just being very intentional about what you're doing and not doing it on your own. 
Doing it as a community, as a group, and doing work before you start doing the work,” she said.  “You have to understand the plant. You have to identify the plant. You have to understand the treatment options for that plant. You have to evaluate, is it actually going to be a big problem? When do we act, and then how do we act? And then, we don't just stop once we're done. We have to monitor, see what worked.”

Once the invasives are removed, the area ideally revegetates spontaneously with native plants. Sometimes, though, the ecosystem needs a little help.

Amy Erfling is the regional greenhouse coordinator for Tlingit and Haida. She’s been experimenting with growing native berries from seed at Taay Hít, which translates to garden house in Lingít. 

“We wanted to be doing this from seed to maintain genetic diversity,” Erfling said. “It kind of depends on the species, but a part of it is fermenting the plants or fermenting the berries.”

She said the berries are blended at low speeds to separate the pulp from the seed, and then go into the fridge for a cold stratification period. So far, the greenhouse has held thimbleberries, blueberries, salmonberries, and willow cuttings. 

“We're not looking at becoming a retail nursery, but we're really focused on the program,” she said. “As Reed mentioned, really imagining what we can do with these areas where we're taking out invasive plants and being able to put locally grown, locally adapted native plants, and hopefully also not be bringing in other potential pests from the Lower 48.”

Reed said that while she hoped the first community weed-pulling events would happen in the next few weeks, details about how the community can get involved in invasive plant management would be coming soon at their website.

“It's not just ‘This is a bad plant. Let's get rid of it.’ It's about caretaking of the land and of the resources that we value.” Reed said. “The plant is out of space because of something that humans did, and so we as humans are working to take care of the land to maintain that ecological integrity.”

• Contact Ellie Ruel at ellie.ruel@juneauindependent.com.