Reed Canarygrass
Phalaris arundinacea
Reed Canarygrass is a very tall grass with wide leaf blades that are nearly perpendicular to the stalk, long flower/seed heads, and is often a brighter green than our native grasses. A variegated cultivar called ribbongrass is often sold as a landscaping plant. Reed Canarygrass is a threat to salmon, as it alters water flow and can take over salmon spawning habitat when it invades stream and river banks. Left unchecked, it forms dense monoculture infestations, preventing other native plants from growing. Invasive wetlands species also alter the composition of insects and other invertebrates near our waterways, which can negatively impact the salmon who eat invertebrates (particularly in their early stages of development).

White Sweetclover
Melilotus alba (=Melilotus albus)
A single plant was found and removed from the Kodiak road system. Had it gone to seed, we may have seen large-scale infestations of this species similar to several places in mainland Alaska that are infested with sweetclover. A very similar plant, yellow sweetclover, is also highly invasive and not native to Kodiak. There are no close lookalikes of native Kodiak plants to sweetclover. Please report any plant you may suspect to be invasive to our office.  

Meadow Hawkweed
Hieracium caespitosum (=Pilosella caespitosa)
There is only one known location of Meadow Hawkweed on Kodiak (in a residential area). Can sometimes be confused with the native Woolly Hawkweed, Hieracium triste (=Pilosells tristis), which is usually found in alpine and subalpine habitats. The native hawkweed has very woolly buds that are usually gray to black.

Orange Hawkweed
Hieracium aurantiacum (=Pilosella aurantiaca)
The most widespread of Kodiak's invasive species, orange hawkweed spreads by seed and also by rhizomes and stolons (runners). It is reportedly allelopathic, producing phytotoxic chemicals in its pollen grains that inhibit seed germination, seedling emergence, or regeneration of other plants. It forms dense monoculture patches when left unmitigated. It appears to offer little to no food value to bears, unlike the biodiverse native ecosystems it invades. While pollinators may visit blooming hawkweed, it does not support the larvae of many native insects such as butterflies and moths that require specific larval food plants and cannot eat hawkweed.

Himalayan Blackberry/Armenian Blackberry
Rubus discolor (=Rubus armeniacus)
Only one location of Himalayan Blackberry has been found on the archipelago to date, and it has since been eradicated. It is a widespread invasive in the Pacific Northwest, forming dense thickets and displacing native species. This species has very thick, thorny stems, with leaves that consist of 5 stalked leaflets.  

Creeping/Canada Thistle
Cirsium arvense
Creeping Thistle is an invasive species that was likely introduced multiple times as a contaminant of feed, potted plants, and other agricultural products. It is now on the state prohibited and noxious weeds list. Creeping thistle has smooth, glossy leaves unlike than bull thistle (with hairy leaves), which is also found in Kodiak. There are no native thistles to Kodiak, and both of these purple-flowering thistles are considered highly invasive in Alaska.  

Siberian peashrub
Caragana arborescens
There are few confirmed peashrub plants growing on the Kodiak Archipelago. While they are considered highly invasive, they may be more manageable in our wet climate than in the drier parts of the state where they are more aggressively spreading.

Chokecherry
‍Prunus virginiana
Often planted as an ornamental, the leaves of this tree can be green, reddish, or purple. Calyxes are as wide as they are long (green triangular structures extending between the petals as shown in the 1st photo). When chopped down or under stress, this tree sends out "sucker" plants and can be difficult to remove once established.  

English/Common Ivy
Hedera helix
‍Only known to be growing around homes in a few locations around Kodiak, and currently not known to have escaped into any natural areas here. This species is known to cause exterior damage to buildings and can be found covering trees and forest floors, shading out native species in places where it has escaped into the wild.

Creeping Buttercup
Ranunculus repens
Common in the vicinity of the city of Kodiak and Bells Flats, this species seems to be especially well-suited for Kodiak's climate and ecosystem. It is toxic to grazing animals. It completely carpets areas where it is allowed to thrive. Smaller patches can be controlled with herbicide, but it is very difficult to eradicate larger infestations.

Yellow Toadflax/Butter & Eggs
Linaria vulgaris
Currently, we have relatively few infestations of this plant around Kodiak. However, some gardeners may have these in their garden without knowing how invasive it can be. There are very few effective methods to eradicate this plant, and it can aggressively spread on its own. Resembling a snapdragon (Antirrhinum spp.), it can easily be mistaken for that common garden plant. Unlike snapdragons, toadflax flowers have a spur on the back/base of each flower and also has thinner leaves.

English Holly
‍Ilex aquifolium
Only two locations known in Kodiak. It is an invasive species throughout the Pacific Northwest and Alaska, invading woodlands and natural areas. If more were planted, the flowers could get pollinated and allow the fruits to form and then be spread by birds.

Tansy ragwort
‍Senecio jacobaea
With only a few known infestations on the archipelago, KSWCD's goal is complete eradication of this species. Most recently, it has been discovered in the Bells Flats area. Please report ANY sightings of this species or similar-looking plants to KSWCD. We can help assist you with identification, removal, and proper disposal of these plants. Please do not move any parts of this plant without asking about proper disposal methods. Mowing is not effective, as it just "trains" the plants to flower at a lower height. A single plant can produce thousands to tens of thousands of seeds, and any nearby soil should be considered contaminated with its seeds as well. Tansy ragwort is toxic, sickening and even killing livestock. Bees that utilize tansy ragwort can product toxic honey. It is reportedly phytotoxic and therefore should be handled with care.

Bull Thistle
‍Cirsium vulgare
This species has mostly been documented along roadsides and highly disturbed, but it has been found escaping into natural areas on the Kodiak Archipelago. Not only are the prickles a nuisance, its seeds can persist in the soil for a long time, possibly 20 years or more.

Oxeye Daisy
Leucanthemum vulgare
Commonly planted in gardens and cemeteries, this beautiful flower is hiding an aggressive nature. We have found it completely taking over native wildflower meadows and natural areas, greatly reducing the biodiversity of the ecosystems it invades. While pollinators may visit them, many of our native insects specialize on particular native species and cannot utilize these plants.

Common Tansy
Tanacetum vulgare
Tansy has been planted by gardeners. While it is appreciated for its cute flowers and ethnobotanical uses, it is known to take over large areas when unmanaged. Old Harbor has an extensive tansy infestation, demonstrating its ability to thrive in our climate.

Tall Buttercup
Ranunculus acris
Common in disturbed areas, tall buttercup is an aggressive seeder. They can spread into natural areas and form monocultures in the right conditions.

Narrowleaf Hawksbeard  / Crepis
Crepis tectorum

Bird's Foot Trefoil Lotus uliginosus
The two records of Lotus uliginosus on Kodiak are the first records for the state for this species. It's highly invasive relative, Lotus corniculatus (AKEPIC rank 65), is sold in local "wildflower" seed mixes and may also become established.