Invasiveness Ranking System for Non-Native Plants of Alaska

Level of effort required (0–4) 3Mechanical and chemical control methods can be used forcontrol of Tatarian honeysuckle. Treatment must be repeatedfor at least 3–5 years in order to stop new plants emerging fromthe seed bank (Batcher and Stiles 2001, Butterfield et al. 1996,WDNR 2004).Total for Feasibility of Control 6/10Total score for 4 sections 65/98§Lupinus polyphyllus ssp. polyphyllus Lindl.Ranking SummaryEcoregion known or expected to occur inSouth CoastalInterior BorealArctic AlpineYesYesYesPotential Max. ScoreEcological Impact 40 14Biological Characteristics and Dispersal 25 16Amplitude and Distribution 25 17Feasibility of Control 10 8Relative Maximum 55Climatic ComparisonCollected inAlaska regions?CLIMEXsimilarity?South Coastal Yes –Interior Boreal Yes –Arctic Alpine No YesSpecial Note–nativity: Lupinus polyphyllus is native to westernNorth America (USDA, ARS 2004) and has now becomenaturalized in Europe (Jennersten et al. 1988, Lid & Lid 1994).Most authors consider bigleaf lupine to be non-native in Alaska(Hultén 1968, Welsh 1974, Densmore et al. 2001). It has beenwidely seeded on roadsides in south-central Alaska (Densmoreet al. 2001). It is well-established in open to dense mixed forests,often near habitations from Fairbanks to southern Alaska whereit is especially common in the Anchorage vicinity (Hultén 1968,Welsh 1974). This species is particularly abundant in burns inMatanuska–Susitna Valley (Lapina pers. obs.). It is present indisturbed areas in Seward (Densmore et al. 2001), has beenreported from Mitkof Island and the Kenai Peninsula (UAM2003). Greater study, using collection records, molecular andmorphological markers, and paleoecological methods arenecessary to confirm the suspected non-nativity of this species inAlaska.Lupinus polyphyllus has been collected in Seward, Denali NationalPark and Preserve, (Densmore et al. 2001), Kenai Peninsula,Mitkof Island, Matanuska–Susitna Valley (UAM 2004). It hasbeen reported established in mixed forest from Fairbanks toAnchorage (Welsh 1974). Using the CLIMEX matching program,climatic similarity between Nome and areas where the species isdocumented is high. Range of the species includes Anchorage andFairbanks (Welsh 1974), which has a 61% and 56% climatic matchwith Nome respectively.common names: bigleaf lupine,marsh lupineEcological ImpactScoreImpact on Ecosystem Processes (0–10) 5Bigleaf lupine is likely to delay the establishment of native speciesin disturbed sites (Densmore et al. 2001). As a nitrogen-fixer, itlikely alters soil conditions (USDA 2002).Impact on Natural Community Structure (0–10) 3Bigleaf lupine establishes in an existing layer and increases thedensity of the layer (Lapina pers. obs.).Impact on Natural Community Composition (0–10) 1Bigleaf lupine appears to integrate into native populations at arelatively low density. Other species do not seem to be stronglyimpacted by its presence (M.L. Carlson pers. obs.)Impact on Higher Trophic Levels (0–10) 5Bigleaf lupine hybridizes freely with Nootka lupine (L.nootkatensis Donn ex Sims) (Welsh 1974). Bigleaf lupine is animportant floral resource for bumblebees (Jennersten et al. 1988),potentially impacting other native plants.Total for Ecological Impact 14/40Biological Characteristics and Dispersal ScoreMode of Reproduction (0–3) 2The plant reproduces from moderate amounts of seed and alsoforms extensive clones from creeping rhizomes (Densmore et al.2001).Long-distance dispersal (0–3) 0The pods open explosively, scattering seeds a few meters. There isno potential for long-distance dispersal (Densmore et al. 2001).Spread by humans (0–3) 3Bigleaf lupine is cultivated as an ornamental, often escaping andbecoming locally well-established (Densmore et al. 2001, Welsh1974). It is spreading along the roads in Alaska (Hultén 1968).Allelopathic (0–2) 0UnknownCompetitive Ability (0–3) 3Bigleaf lupine is moderately competitive for limiting factors; alsoit has the ability to fix nitrogen (Densmore et al. 2001, USDA2002).Thicket-forming/Smothering growth form (0–2) 0Bigleaf lupine is a perennial herb with stems to 5-feet tall (Pojarand MacKinnon 1994). In Alaska it rarely grows that tall and doesnot grow very densely (M.L. Carlson pers. obs.)Germination requirements (0–3) 2Bigleaf lupine can germinate in vegetated areas (Densmore etal. 2000, I. Lapina pers. obs.). The seeds require scarification forsuccessful germination.B-71