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BLM National List of Invasive Weed Species of Concern

The definition of "weed" is always debatable. Traditional definitions include "plants out of place" or "plants that by their presence conflict with management objectives for the site." The definition included here also tries to incorporate the concepts of public land health and sustainability. A weed is defined as "a non native plant that disrupts or has the potential to disrupt or alter the natural ecosystem function, composition and diversity of the site it occupies. It 's presence deteriorates the health of the site , it makes efficient use of natural resources difficult and it may interfere with management objectives for that site. It is an invasive species that requires a concerted effort (manpower and resources) to remove from its current location, if it can be removed at all." This definition is adapted from Noss and Cooperider (1994) and Beck (personal communication).

"Noxious" weeds refer to those plant species which have been legally designated as unwanted or undesirable. This includes national, state and county or local designations. According to the Federal Noxious Weed Law, native plant species are not designated "noxious". Native plant species that may be of a management concern, such as poisonous plants or desert shrub and sub-shrub species are not considered priorities for noxious weed work or funding and are not included on the following list.

All weeds are not of equal importance for management. The focus of this list is on exotic species that are highly invasive in natural systems. Those species that are of a concern in agricultural situations, but do not pose a threat to rangelands, forestlands and wetlands have not been included. Many annual forbs have not been included. Exotic species typically used in range restoration which are known to be invasive have not been included. Invasive annual grasses which disrupt natural ecosystem function have been included.

Scientific NameCommon NameFamily
Aegilops cylindricajointed goatgrassPoaceae
Ammophila arenariaEuropean beachgrass Poaceae
Arundo donaxgiant reed Poaceae
Bromus diandrusripgut brome Poaceae
Bromus japonicusJapanese brome Poaceae
Bromus rubensred brome Poaceae
Bromus tectorumdowny brome Poaceae
Cenchrus longispinus longspine sandbur Poaceae
Cortaderia jubata Andean pampas grass Poaceae
Cortaderia selloanapampas grass Poaceae
Cynodon dactylonbermudagrass Poaceae
Ehrharta calycina veldt grass Poaceae
Elytrigia repensquackgrass Poaceae
Eragrostis lehmannianaLehmann lovegrassPoaceae
Nardus strictamatgrass Poaceae
Panicum miliaceumwild proso milletPoaceae
Pennisetum setaceum crimson fountain grass Poaceae
Schismus arabicusschismus Poaceae
Schismus barbatus mediterranean grass Poaceae
Sorghum halepensejohnsongrass Poaceae
Taeniatherum caput-medusae medusa-head Poaceae
Acroptilon repens Russian knapweedAsteraceae
Anthemis arvensisscentless chamomile Asteraceae
Anthemis cotulamayweed chamomileAsteraceae
Arctium minuscommon burdock Asteraceae
Bassia hyssopifoliabassia BasellaceaeAsteraceae
Brassica nigrablack mustardBrassicaceae
Brassica tournefortii wild turnipBrassicaceae
Caesalpinia gilliesiiMexican bird-of-paradiseFabaceae
Cardaria chalepensislens-podded whitetopBrassicaceae
Cardaria drabahoary cress Brassicaceae
Cardaria pubescenshairy whitetop Brassicaceae
Carduus acanthoides plumeless thistle Asteraceae
Carduus nutansmusk thistleAsteraceae
Carduus pycnocephalusItalian thistle Asteraceae
Carduus teniflorusslender-flowered thistle Asteraceae
Carpobrotus edulis hottentot fig Aizoaceae
Carpobrotus chilensissea iceplant Aizoaceae
Carthamus lantus distaff thistleAsteraceae
Carum carvicommon carawayApiaceae
Centaurea calcitrapa purple starthistle Asteraceae
Centaurea cyanus cornflower Asteraceae
Centaurea diffusadiffuse knapweed Asteraceae
Centaurea ibericaIberian starthistle Asteraceae
Centaurea jacea brown knapweed Asteraceae
Centaurea macrocephala bighead knapweed


Centaurea maculosaspotted knapweedAsteraceae
Centaurea melitenisismalta starthistleAsteraceae
Centaurea montanamountain cornflowerAsteraceae
Centaurea nigrablack knapweed Asteraceae
Centaurea nigrescensVochin knapweedAsteraceae
Centaurea pratensismeadow knapweed Asteraceae
Centaurea squarrosa squarrose knapweed Asteraceae
Centaurea solstitialis yellow starthistleAsteraceae
Centaurea trichocephala feather-headed knapweedAsteraceae
Chondrilla juncearush skeletonweedAsteraceae
Chrysanthemum leucanthemumox-eye daisyAsteraceae
Cichorium intybuschicory Asteraceae
Cirsium arvense Canada thistleAsteraceae
Cirsium vulgarebull thistleAsteraceae
Clematis orientalis Chinese clematisRanunculaceae
Conium maculatumpoison hemlockApiaceae
Convolvulus arvensis field bindweedConvoluvaceae
Crepis setosabristly hawkweedAsteraceae
Crupina vulgariscommon crupinaAsteraceae
Cynara cardunculus artichoke thistleAsteraceae
Cynoglossum officinalehoundstongueBoraginaceae
Digitalis purpureafoxglove Scrophulariaceae
Dipsacus fullonumcommon teasel Dipsacaceae
Echium vulgareblueweedBoraginaceae
Egeria densaBrazillian waterweedHydrocharitaceae
Eichhornia crassipeswater hyacinth Hydrocharitaceae
Erechtites glomerataAustralian fireweedAsteraceae
Euphorbia cyparissiascypress spurgeEuphorbiaceae
Euphorbia esulaleafy spurgeEuphorbiaceae
Euphorbia myrsinitesmyrtle spurgeEuphorbiaceae
Foeniculum vulgarefennel Apiaceae
Galega officinalis goats rue Fabaceae
Gypsophila paniculatababys breathCaryophyllaceae
Halogeton glomeratushalogetonChenopodiaceae
Hesperis matronalisdames's rocketBrassicaceae
Hieracium aurantiacum orange hawkweedAsteraceae
Hieracium pilosella mouseear hawkweedAsteraceae
Hieracium pratense yellow hawkweed Asteraceae
Hydrilla verticillatahydrilla Hydrocharitaceae
Hyoscyamus nigerblack henbaneSolanaceae
Hypericum perforatumcommon St. JohnswortHypericaceae
Hyposhaeris radicatacommon catsearAsteraceae
Isatis tinctoria dyer's woad Brassicaceae
Knautia arvensis blue buttonsDipsacaceae
Lathyrus latifoliuseverlasting peavineFabaceae
Lepidium latifoliumperennial pepperweed Brassicaceae
Linaria genistifolia spp. dalmatica dalmation toadflaxScrophulariaceae
Linaria vulgarisyellow toadflax Scrophulariaceae
Lysimachia vulgaris garden loosestrifePrimulaceae
Lythrum salicaria purple loosestrifeLythraceae
Lythrum virgatumwand loosestrifeLythraceae
Madia sativa Chilean tarweed Asteraceae
Myriophyllum spicatumEurasian watermilfloil Haloragaceae
Onopordum acanthiumScotch thistle Asteraceae
Onopordum taricum Scotch thistleAsteraceae
Peganum harmala African rue Zygophyllaceae
Potentilla recta sulphur cinquefoilRosaceae
Salvia aethiopsis Mediterranean sageLamiaceae
Saponaria officinalis bouncing bet Caryophyllaceae
Senecio jacobaeatansy ragwortAsteraceae
Senecio mikanoidesGerman ivy Asteraceae
Solanum dulcamarabitter nightshade Solanaceae
Sonchus arvensisperennial sowthistleAsteraceae
Sphaerophysa salsula swainsonpea Fabaceae
Tanacetum vulgarecommon tansyAsteraceae
Zygophyllum fabagoSyrian bean caperZygophyllaceae
Shrubs and Trees
Ailanthus altissima tree-of-heavenSimaroubaceae
Alhagi pseudalhagi camelthorn Fabaceae
Cytisus junceum Spanish broom Fabaceae
Cytisus monspessulanasFrench broomFabaceae
Cytisus scopariusScotch broomFabaceae
Cytisus striatusPortugese broomFabaceae
Elaeagnus angustifoliaRussian oliveElaeagnaceae
Ficus caricaedible figMoraceae
Lespedeza cuneataHimalayan bush cloverFabaceae
Retama monospermabridal veil broomFabaceae
Rubus discolorHimalaya blackberryRosaceae
Schinus terebrinthifoliusBrazillian pepperAnacardiaceae
Tamarix aphyllaathelTamaricaceae
Tamarix chinensistamariskTamaricaceae
Tamarix gallicaFrench tamariskTamaricaceae
Tamarix parviflorasmall flower tameriskTamaricaceae
Tamarix pentandatamariskTamaricaceae
Tamarix ramosissimasalt cedarTamaricaceae
Ulex europaeusgorseFabaceae
Ulmus pumilaSiberian elmUlmaceae