All species accounts were taken from the Invasive Plants of Alaska guide published by the Alaska Association of Conservation Districts in 2005.

Asteraceae (Sunflower Family) species of greatest concern
Centaurea biebersteinii, spotted knapweed
Cirsium arvense, Canada thistle
Cirsium vulgare, bull thistle
Hieracium aurantiacum, orange hawkweed and other hawkweeds
Leucanthemum vulgare, oxeye daisy
Senecio jacobaea, tansy ragwort
Sonchus arvensis ssp. uliginosus, perennial sowthistle
Tanacetum vulgare, common tansy
Tragopogon dubius, western salsify
Tripleurospermum perforata, scentless false mayweed

Asteraceae (Sunflower Family) species of lesser concern
Cotula coronopifolia, brassbuttons
Crepis tectorum, narrowleaf hawksbeard
Hypochaeris radicata, spotted catsear
Lactuca serriola, prickly lettuce
Lapsana communis, nipplewort
Leontondon autumnalis, hawkbit
Matricaria discoidea, pineapple weed
Mycelis muralis, wall lettuce
Taraxacum officinale ssp. officinale, common dandelion

Brassicaceae (Mustard Family) species of greatest concern
Alliaria petiolata, garlic mustard

Brassicaceae (Mustard Family) species of lesser concern
Brassica rapa, birdsrape mustard
Capsella bursa-pastoris, shepherd’s purse
Descurainia sophia, flixweed
Hesperis matronalis, sweetrocket
Lepidium densiflorum, common peppergrass
Rorippa austriaca, Austrian yellowcress
Thlaspi arvense, fi eld pennycress

Fabaceae (Pea Family) species of greatest concern
Melilotus alba, white sweetclover
Vicia cracca, bird vetch

Fabaceae (Pea Family) species of lesser concern
Lupinus polyphyllus, bigleaf lupine
Medicago lupulina, black medick
Trifolium hybridum, alsike clover

Poaceae (Grass Family) species of greatest concern
Bromus tectorum, cheatgrass
Elymus repens, quackgrass
Phalaris arundinacea, reed canarygrass
Spartina alterniflora, smooth cordgrass

Poaceae (Grass Family) species of lesser concern
Dactylis glomerata, orchardgrass
Hordeum jubatum, foxtail barley
Lolium perenne, Italian ryegrass
Phleum pratense, common timothy
Poa pratensis, Kentucky bluegrass

Polygonaceae (Buckwheat Family) species of greatest concern
Polygonum cuspidatum, Japanese knotweed

Polygonaceae (Buckwheat Family) species of lesser concern
Polygonum aviculare, prostrate knotweed
Polygonum convolvulus, black bindweed
Rumex acetosella, common sheep sorrel

Species of greatest concern in other families
Heracleum mantegazzianum, giant hogweed (Apiaceae (Carrot) Family)
Impatiens glandulifera, ornamental jewelweed (Balsaminaceae (Balsam) Family)
Euphorbia esula, leafy spurge (Euphorbiaceae (Spurge) Family)
Myriophyllum spicatum, Eurasian watermilfoil (Haloragaceae (Water Milfoil) Family)
Galeopsis bifida, hempnettle (Lamiaceae (Mint) Family)
Lythrum salicaria, purple loosestrife (Lythraceae (Loosestrife) Family)
Linaria vulgaris, yellow toadflax (Scrophulariaceae (Figwort) Family)

Less Aggressive Species
Lappula squarrosa, bluebur (Boraginaceae (Borage) Family)
Myosotis scorpioides, marsh forget-me-not (Boraginaceae (Borage) Family)
Saponaria officinalis, bouncingbet (Caryophyllaceae (Pink) Family)
Silene noctiflora, night-blooming cockle (Caryophyllaceae (Pink) Family)
Spergula arvensis, corn spurry (Caryophyllaceae (Pink) Family)
Stellaria media, common chickweed (Caryophyllaceae (Pink) Family)
Chenopodium album, lambsquarters (Chenopodiaceae (Goosefoot) Family)
Hypericum perforatum, common St. Johnswort (Clusiaceae (Mangosteen) Family)
Convolvulus arvensis, field bindweed (Convolvulaceae (Morning-glory) Family)
Plantago major, common plantain (Plantaginaceae (Plantain) Family)
Ranunculus repens, creeping buttercup (Ranunculaceae (Buttercup) Family)
Digitalis purpurea, foxglove (Scrophulariaceae (Figwort) Family)
Euphrasia nemorosa, common eyebright (Scrophulariaceae (Figwort) Family)

Trees and Shrubs to Watch
Lonicera tatarica, bush honeysuckle (Caprifoliaceae (Honeysuckle) Family)
Daphne laureola, spurge laurel (Thymeliaceae (Mezereum) Family)
Caragana arborescens, Siberian peashrub (Fabaceae (Pea) Family)
Cytisus scoparius, scotchbroom (Fabaceae (Pea) Family)
Pinus contorta var. latifolia, lodgepole pine (Pinaceae (Pine) Family)
Prunus padus, European bird cherry (Rosaceae (Rose) Family)
Sorbus aucuparia, European mountain ash (Rosaceae (Rose) Family)