Wearing a pump-powered backpack sprayer, long yellow gloves and protective goggles, Jen Peura looked more like she was out hunting ghosts than killing flowers.
The seasonal biotech for the Kenai National Wildlife Refuge pointed to a thin, leafy sprig near the narrow Egumen Lake trail. The innocuous-looking plant blended in with the grasses around it, bearing only a small knot of a bud at the top.
“If you look over there, those are just everywhere,” she said, sweeping a hand toward the embankment obscured by grasses and bright spots of purple lupine. “We’ll just get these, but those are close to the roadway and just getting rained with seeds all the time.”
A squirt of herbicide on the little sprout does the trick. Further back toward the trailhead, the spiky fans of common dandelion leaves grow happily through gravel and dirt, but these Peura leaves alone. The battle with dandelions is more or less a lost cause, she said — they are everywhere, and the amount of time, effort and herbicide that would go into killing them makes the fight not worth it. However, there are some plants botanists, biotechs and volunteers are fighting to keep off the peninsula. Oxeye daisy, for example — a pretty white flower with a bright yellow center — is an invasive plant with a stronghold in Seward currently trying to make incursions into the central and lower Kenai Peninsula.
“Even someone from Seward who just drives over for a hike and doesn’t brush off their shoes can bring it on their shoes or tires,” Peura said.
Controlling invasive plants is a defensive game — there’s no way to go out and eliminate the plants from ever coming into Alaska, and the state does not dictate what private landowners can and cannot plant on their property.
The best approach to treatment is to discover the plant early in its colonization, while the population is still small and easy to treat in a small space. Once it has spread and established populations in multiple locations, it can be expensive and difficult to fight, said Matt Steffy, a resource specialist with the Homer Soil and Water Conservation District who coordinates the district’s invasive plants program and works with the Kenai Peninsula Cooperative Weed Management Area.
Government, nonprofit and private donors spent about $29 million to manage invasive species in Alaska from 2007–2011, about $5.8 million per year, according to a 2012 analysis from the University of Alaska Anchorage’s Institute of Social and Economic Research. About 41 percent of that spending went toward controlling and researching invasive land plants, according to the report.
Despite the spending, some of the plants are still spreading in Alaska, and in Anchorage particularly, Steffy said. The Kenai Peninsula is slightly more protected by its geography, he said.
“In some of these areas or on some of these weeds, we’re starting to slip into some of (the out-of-control) level,” Steffy said. “Terrestrially, (the Kenai Peninsula has) a very narrow neck of connection to the rest of the state. We have a geographic opportunity to maintain isolation.”
Invasive plants arrive in Alaska a number of ways: by hitching a rides on cars, migrating birds, boats or people. Sometimes they are voluntarily brought as well, either for a practical purpose or for decoration, Steffy said. For example, both reed canary grass and bird vetch were introduced to the Kenai Peninsula as experimental forage crops before they escaped cultivation and invaded wetlands and riverbanks. Another aggressive invasive plant, the orange hawkweed, was introduced to Seldovia as an ornamental flower.
Once a plant gets out of control, the land mangers have to decide whether to expend the resources to control it, Peura said. The refuge doesn’t have as severe of a dandelion infestation as other parks in Alaska, but the populations that do exist are difficult to control because their seeds are spread by wind.
“We’ve kind of given that over,” Peura said. “Once you have to put down a lot of herbicide to get rid of it, it’s not really worth it, and you could hand-pull forever.”
Control Through Cooperation
The peninsula may have a set of different land managers for its regions, but they work together to take out the invasive species in the ecosystem.
One major upcoming project for the Homer Soil and Water Conservation District, partnering with the Department of Transportation through its Integrated Vegetation Management Plan, focuses on controlling bird vetch, a particularly aggressive climbing plant that covers trees and road signs. The population grows “absurdly” thick in other parts of the state, but it is limited enough on the Kenai Peninsula to give managers a chance to control it, Steffy said.
Another way to curb invasive plants is to make sure the gravel used in construction projects are weed free. With big upcoming construction projects on the peninsula like the Sterling Highway reroute around Cooper Landing, the potential for invasive species to be spread through gravel is concerning, Steffy said. However, the Cooperative Extension Service and the soil and water conservation districts now inspect gravel pits to make sure they are “weed-free,” ensuring that the material taken from there does not have actively growing invasive weeds.
The gravel pit owners get the added benefit of possibly being able to charge more for added value to their product, Steffy said. The certification does not ensure that the pits are 100 percent weed free, only that there are no invasive plants actively growing — some seeds can live for decades underground, he said.
“We’ve moved from having one gravel pit on the peninsula certified to having four or five right now that are in the certification process,” Steffy said. “There’s going to be a lot of yardage required for the projects taking place this season.”
Construction is not the only industry working to help curtail invasive plants on the peninsula. The refuge is working with Hilcorp in its Swanson River lease holding to help control invasive species there. The company coordinates the work and the refuge sends out workers to help, Peura said.
One major invasive plant, elodea, has seemingly been beaten back off the peninsula. Refuge managers first identified the prolific aquatic plant in Kenai Peninsula lakes in 2012, but after several chemical shocks and spot treatments, the lakes appear to be elodea-free. Refuge managers will continue to monitor for the plant, and Steffy said he still works with other land managers in Prince William Sound and Anchorage on the projects to eliminate elodea in fresh water there.
Steffy sometimes gets calls from Homer residents asking what they should do with a type of weed they found.
“Usually within three or four questions, I’ll be able to identify it,” he said.
The Homer Soil and Water Conservation District organizes community pulls and education across Kachemak Bay in the remote communities of Seldovia, Nanwalek and Port Graham, encouraging residents to know the differences between native and invasive plants and how to control them. Mowing kills some plants but spreads others; hand-digging removes some plants but leaves enough roots from others to do nothing but delay the growth.
On the refuge, each trailhead has a boot brush and basin to catch falling invasive species’ seeds. Peura said it works best if hikers dust off their boots before they enter the trail rather than after leaving.
“That way, the seeds don’t make it in in the first place, and all the invasives would concentrate right here,” she said.
The Chugach National Forest, managed by the U.S. Forest Service, also plays a role in managing the species, often working with the Kenai Peninsula Cooperative Weed Management Area, said Alisha King, a spokesperson for Chugach National Forest.
One species forest managers watch specifically is the reed canary grass near Russian River, a traffic-heavy riverbank. Young volunteers who kayak in Prince William Sound, also a part of the forest, often pull dandelions as part of their invasive species work, King said. Every five years, forest managers also evaluate the areas near the roads for invasive species, she said.
“We have a list of priority plants that we’re working on,” King said.
Although it wouldn’t hurt for residents and visitors to pull up dandelions when they see them, Peura said they probably should not pull up plants whenever they see them — it’s possible to mistake two similar species. For instance, many grasses look similar, and Alaska has both an invasive and a native species of buttercup. The University of Alaska Anchorage’s Alaska Center for Conservation Science has a full list of invasive species on its website, and the Cooperative Extension Service developed an app, Alaska Weeds ID, that provides a field guide to invasive species and allows users to send reports and pictures of invasive species they find in the field to the Cooperative Extension Service in Anchorage.
Steffy said people should always be aware of property ownership when they are pulling weeds, as it is illegal to pull plants from private property without permission. Instead, it would be better for the property owner to learn why they should get rid of the plant themselves, he said.
“It’s not that (the plants) are illegal, and so if a landowner chooses to have even a particularly problematic weed on their property, that is their choice,” Steffy said. “At the end of the day, it is a lot of education.”
Reach Elizabeth Earl at firstname.lastname@example.org.