Invasive Species Prohibited Plant List The introduction of non-native, invasive plant species on City lands has had increasing environmental and financial impacts. Every year the City of Eugene has continued to prioritize the restoration and renovation of sensitive habitat areas such as the West Eugene Wetlands, Hendricks Park Forest, Whilamut Natural Area of Alton Baker Park, Ridgeline Trail, and Spencer and Skinner buttes. Still invasive plants are frequently found out-competing our native species, threatening food, habitat and genetic diversity of plants and wildlife. In an effort to halt the intentional introduction of invasive species and to promote the re- introduction of native species, the City has a policy that prohibits the use of the most problematic and documented invasive species, discourages the planting of other species that are suspected to be problematic, and encourages the use of native plants on all City-owned lands and projects. The following plants have been determined highly invasive and may not be planted or utilized on City property or City projects. Scientific Name Common Notes Reference Name Acer platanoides Norway Invasive tree spreading into forested 3, 4 maple natural areas around town including Skinner's Butte. Ailanthus altissima tree-of- Invasive tree that is problematic in City 2, 3, 4 heaven parks, alleys, and undeveloped property. This species is capable of becoming established through cracks in concrete. Alliaria petiolata garlic One of the most invasive forest understory 1, 4 mustard plants in the east and midwest, starting to establish in the Seattle area. Documented as present in Portland and Eugene. Arum italicum Italian arum Invasive plant starting to establish. 4 Documented as present in Portland and Eugene. Betula European This species is spreading rapidly along 2, 4 pendula/pubescens birch waterways and is now established along the entirety of Amazon Creek from near its headwaters to Fern Ridge Reservoir. Brachypodium false-brome Highly invasive grass rapidly spreading 1, 2, 3, 4 sylvaticum through forests and along rivers in our City of Eugene – Invasive Species Prohibited List Page 1 of 7 area in numerous places including Alton Baker Park. It has the potential to permanently alter the forest understory, as it outcompetes most other species and no control is known. Buddleia butterfly bush Both butterfly bushes displace native 1, 4 alternifolia willows which are essential host plants for B. davidii native butterflies. B. varabilis Carex pendula drooping Invasive plant starting to establish. 4 sedge Documented as present in Portland and Eugene. Carex divulsa grassland Invasive plant starting to establish. sedge Common in the nursery trade, being sold as Carex tumulicola, documented as present in Portland and Eugene. Centaurea meadow Tall perennial found along roadsides, fields 1, 4 pratensis knapweed and pastures. This is the only knapweed common in our area. There is a large population in West Eugene along Fir Butte Road and on surrounding properties. Cirsium arvense Canada This thistle propagates rhizomonously 1, 4 thistle from deep and extensive horizontal roots making it challenging to control. It can be found along roadsides and in disturbed natural areas throughout the region. Cirsium vulgare bull thistle This biennial thistle has a short, fleshy 1, 4 taproot. This spiny thistle can be found throughout the area in disturbed areas, along roadsides, and pastures. Clematis vitalba traveler's-joy Invasive climber comparable to English ivy 1, 2, 3, 4 as a problem in areas of Portland and Seattle. Currently appearing in several areas along the Willamette with large populations established on Skinner Butte. Conium maculatum poison Widespread invader along the Willamette 1, 4 hemlock River corridor. This plant is toxic and can cause skin irritation when touched. Convolvulus field Common in gardens; seen in some natural 4 arvensis bindweed areas such as Willow Creek Natural Area Crataegus English This species is well established and 2, 4 monogyna hawthorn spreading rapidly into woodlands and prairies throughout town. It interbreeds with the native hawthorn creating hybrids that are difficult to accurately identify. City of Eugene – Invasive Species Prohibited List Page 2 of 7 Cynoglossum common This common garden species has escaped 2, 3 officinale houndstongue and appears regularly in several City parks, along waterways and in unimproved alleys. Cyperus esculentus yellow Invasive plant starting to establish. 1 nutsedge Documented as present in Portland and Eugene. Cytisus scoparius Scotch broom Dense populations of Scotch broom have 1, 2, 3, 4 C. striatus Portuguese established along the Willamette, in the broom south hills, throughout the West Eugene Genista French broom Wetlands, along roadways and railways monspessulana and in several city parks. Other broom Spartium junceum Spanish species have also been found in Eugene. broom Avoid use of all brooms. Daphne laureola spurge laurel Spread by birds into forested areas 2, 4 throughout town. Dipsacus fullonum common Invasive plant starting to establish. 4 teasel Documented as present in Portland and Eugene. Digitalis purpurea foxglove This common and attractive garden wild 2 flower escapes easily and forms dense populations. It is becoming well established in some areas along the Willamette River. Fallopia spp. knotweeds These species (F. japonica, F. bohemica, 1, 2, 4 (formerly F. sachalinensis) form riparian Polygonum spp.) monocultures and are very hard to eradicate. There are several small populations in Eugene, but much larger ones in other locations around the county and state. Foeniculum Fennel South side Skinner Butte and North side of 3, 4 vulgare Willamette River. Extensive on south coast and northern California Geranium lucidum shining Beginning to dominate forest understories 1, 4 crane's-bill in south Eugene. Geranium herb robert Dominates forest understories in several 1, 2, 3, 4 robertianum areas in Eugene including Hendrick's park. This species is spreading rapidly throughout town. Hedera helix English ivy Both species spread vegetatively in 1, 2, 4 H. hibernica Atlantic ivy forested and open areas. Seeds spread mostly by exotic birds including starlings. Ivy is an extensive and widespread problem throughout Eugene, especially in City of Eugene – Invasive Species Prohibited List Page 3 of 7 forested areas and along the Willamette River. Hypericum St. John's This species invades meadows, trailsides, 1, 2, 3 perforatum wort roadsides, and other areas throughout town. Ilex aquifolium English holly Spread by birds and appears regularly in 2, 4 forest understories throughout town. Impatiens policeman’s This species is not known in Eugene yet, 1, 3, 4 glandulifera helmet but could invade riparian and wetland habitats, if introduced. Iris pseudoacorus yellow flag Forms monocultures in wetlands. This 1, 3, 4 iris species has established in Bertelsen Slough, Amazon Creek, Flat Creek, Spring Creek and along the Willamette River. Juncus effusus var common rush Invasive plant starting to establish. effusus Common in the nursery trade, being sold as Juncus Effusus var pacificus, documented as present in Portland and Eugene Lamiastrum Yellow This European native mint thrives in forest 1, 4 galeobdolon archangel understory habitat and seems to spread mostly via yard debris dumping Lathyrus latifolius sweet, Well-established, primarily along 1 perennial or roadsides and hedgerows, large everlasting population on Chamber’s connector. Listed pea in “Weeds of the West” Leucanthemum oxeye daisy This species is common in commercial 2, 4 vulgare "wildflower mixes". It has become widely established in meadows in West Eugene, Amazon Park, and along roadsides and mowed waterways. Formerly Chrysanthemum leucanthemum. Linaria vulgaris yellow Roadside weed expanding into prairies. 1, 2, toadflax Lotus corniculatus birdsfoot Sold in pasture mixes. This species has 2, 4 trefoil invaded wetland areas throughout town including most drainage channels. Ludwigia water Aggressive aquatic weed that forms a 3, 4 hexapetala primrose dense floating mass in ponds, lakes, and L. peploides slow moving water bodies. All fragments L. grandiflora of the plant can resprout. Found locally in Golden Gardens ponds, Delta Ponds, and Spring Creek. City of Eugene – Invasive Species Prohibited List Page 4 of 7 Lysimachia creeping Invasive plant starting to establish. 4 nummularia jenny Documented as present in Portland and Eugene. Lythrum salicaria purple This species forms monocultures in 1, 2, 4 loosestrife wetlands and is a species of national concern. Although not yet widespread, populations have been found in Amazon Creek, Delta Ponds, and along the Willamette River. Nymphoides yellow Aggressive aquatic weed that forms a 1, 3 peltata floating heart dense floating mass in ponds, lakes, and slow moving water bodies. This species is very difficult to control once established and is found north of Eugene near the River Ridge Golf Course. Mentha pulegium pennyroyal Widespread in West Eugene Wetlands and 3, 4 other areas with emergent wetlands. Myriophyllum spp. Eurasian Includes water-milfoils. Myriophyllum 1, 2 watermilfoil, aquaticum (M. brasiliense; parrot's parrot’s feather) and M. spicatum (Eurasian feather milfoil) are common aquatic species in waterways and ponds throughout Eugene. Phalaris aquatica Harding grass This wetland species is found in slightly 2 drier conditions than P. arundinacea. While populations are not yet as widespread as P. arundinacea, populations