Source: California Invasive Plant Council
URL of this page: http://www.cal-ipc.org/ip/inventory/weedlist.php
California Invasive Plant Inventory Database
Showing all plants
Filter plants by region:Selecting a floristic province will show only plants found in all regions of that province, not those found in only one or a few regions. Select an individual region to see all plants found there.
> See abbreviation and scores key
> Project description and background
Click on column heading to sort the table. Click on the scientific name for the Plant Assessment Form, or the icon for the Plant Profile. You can also download a tab-delimited file of this data which can be imported into Microsoft Excel or other programs.
Scientific Name | Common Name | Rating | Alert | Imp. | Inv. | Dis. | Doc. | Regions | Habitats of Concern and Comments |
---|---|---|---|---|---|---|---|---|---|
Acacia dealbata | silver wattle | 2Moderate | B | B | B | 2.5 |
|
Coastal prairie, riparian woodland, riparian forest, North Coast coniferous forest, closed cone coniferous forest. | |
Acacia melanoxylon | black acacia, blackwood acacia | 3Limited | C | C | B | 2.7 |
|
Coniferous forest, chaparral, woodland, riparian. Impacts are low in most areas. | |
Acacia paradoxa | kangaroothorn | 4Eval No List | D | C | C | 2.5 |
|
Does not spread in wildlands. | |
Acroptilon repens | Russian knapweed | 2Moderate | B | B | B | 3.2 |
|
Scrub, grasslands, riparian, pinyon-juniper woodland, forest. Severe impacts in other western states. Spreading in many areas of CA. | |
Aegilops triuncialis | barb goatgrass | 1High | A | A | B | 3.6 |
|
Grassland, oak woodland; spreading in NW and in Central Valley. | |
Aeschynomene rudis | rough jointvetch | 4Eval No List | D | C | D | 3.2 |
|
Serious agricultural weed, but not known to have impacts in wildlands. | |
Ageratina adenophora | croftonweed, eupatorium | 2Moderate | B | B | B | 2.8 |
|
Coastal canyons, scrub, slopes. Very invasive in Australia, limited information and distribution in CA. | |
Agrostis avenacea | Pacific bentgrass | 3Limited | C | C | C | 2.4 |
|
Vernal pools, coastal prairie, meadows, grasslands. Impacts are low in most areas. | |
Agrostis stolonifera | creeping bentgrass | 3Limited | C | B | C | 1.9 |
|
Wetlands, riparian; grown for domestic forage. Limited distribution and impacts unknown. | |
Ailanthus altissima | tree-of-heaven | 2Moderate | B | B | B | 3.0 |
|
Riparian areas, grasslands, oak woodland. Impacts highest in riparian areas. | |
Aira caryophyllea | silver hairgrass | 4Eval No List | D | C | A | 2.6 |
|
Widespread in grasslands, but impacts appear negligible. | |
Aira praecox | European hairgrass | 4Eval No List | D | C | C | 2.8 |
|
Appears to be spreading locally, but impacts unknown. | |
Albizia lophantha | plume acacia | 4Eval No List | U | C | C | 1.5 |
|
Present in Golden Gate National Recreation Area. Need more information. | |
Alhagi maurorum | camelthorn | 2Moderate | B | B | B | 3.2 |
|
Grassland, meadows, riparian and desert scrub, Sonoran thorn woodland. Very invasive in southwestern states. Limited distribution in CA. | |
Allium triquetrum | three-cornered leek | 4Eval No List | U | C | C | 1.6 |
|
Impacts unknown. | |
Alternanthera philoxeroides | alligator weed | 1High | Alert | A | B | C | 2.9 |
|
Freshwater aquatic systems, including marshes |
Ammophila arenaria | European beachgrass | 1High | A | B | B | 3.2 |
|
Coastal dunes | |
Anthemis cotula | mayweed chamomile, dog fennel | 4Eval No List | D | B | B | 2.4 |
|
Abiotic and wildife impacts unknown | |
Anthoxanthum odoratum | sweet vernalgrass | 2Moderate | B | B | B | 2.7 |
|
Coastal prairie, coniferous forest. Little information available on impacts and limited ecological range. | |
Arctotheca calendula (fertile) | fertile capeweed | 2Moderate | Alert | B | B | C | 3.6 |
|
Coastal prairie; can produce seed. Important agricultural weed in Australia, but limited distribution in CA. |
Arctotheca calendula (sterile) | sterile capeweed | 2Moderate | B | B | B | 2.8 |
|
Coastal prairie; only propagates vegetatively. More competitive than fertile form, but limited distribution. | |
Arundo donax | giant reed | 1High | A | B | A | 2.8 |
|
Riparian areas, commercially grown for musical instrument reeds, structural material, etc. | |
Asparagus asparagoides | bridal creeper | 2Moderate | Alert | B | B | D | 2.6 |
|
Riparian woodland |
Asphodelus fistulosus | onionweed | 2Moderate | Alert | B | A | C | 2.9 |
|
Coastal dunes, prairie, grasslands. More invasive in Australia. High invasiveness but limited distribution in CA. |
Atriplex semibaccata | Australian saltbush | 2Moderate | B | B | B | 2.9 |
|
Coastal grasslands, scrub, upper salt marsh. Limited distribution, but can be very invasive regionally. | |
Avena barbata | slender wild oat | 2Moderate | B | B | A | 3.5 |
|
Coastal scrub, grasslands, oak woodland, forest. Very widespread, but impacts more severe in desert regions. | |
Avena fatua | wild oat | 2Moderate | B | B | A | 3.2 |
|
Coastal scrub, chaparral, grasslands, woodland, forest. Very widespread, but impacts more severe in desert regions. | |
Bassia hyssopifolia | fivehook bassia | 3Limited | C | C | B | 2.7 |
|
Alkaline habitats. Weed of agriculture or disturbed sites. Impacts minor in wildlands. | |
Bellardia trixago | bellardia | 3Limited | C | C | C | 1.9 |
|
Grasslands, including serpentine. Impacts and invasiveness appear to be minor. | |
Bellis perennis | English daisy | 4Eval No List | D | C | C | 2.8 |
|
Present along trails, not known to spread into undisturbed areas | |
Berberis darwinii | Darwin barberry | 4Eval No List | U | B | D | 2.1 |
|
Impacts unknown | |
Brachypodium distachyon | annual false-brome, false brome, purple false broom, stiff brome | 2Moderate | B | B | B | 2.6 |
|
Valley and foothill grassland, cimontane woodland | |
Brachypodium sylvaticum | perennial false-brome | 2Moderate | Alert | B | A | D | 2.5 |
|
Redwoods and mixed evergreen forest in Santa Cruz Mtns. Expanding range rapidly in OR, potentially very invasive. |
Brassica nigra | black mustard | 2Moderate | B | B | A | 2.0 |
|
Widespread. Primarily a weed of disturbed sites, but can be locally a more significant problem in wildlands. | |
Brassica rapa | birdsrape mustard, field mustard | 3Limited | C | B | B | 1.8 |
|
Coastal scrub, grasslands meadows, riparian. Primarily in disturbed areas, Impacts appear to be minor or unknown in wildlands. | |
Brassica tournefortii | Saharan mustard, African mustard | 1High | A | A | B | 2.3 |
|
Desert dunes, desert and coastal scrub | |
Briza maxima | big quackingrass, rattlesnakegrass | 3Limited | B | C | B | 2.3 |
|
Grasslands. Widespread in coast range. Impacts generally minor, but locally can be higher. | |
Bromus diandrus | ripgut brome | 2Moderate | B | B | A | 3.3 |
|
Dunes, scrub, grassland, woodland, forest. Very widespread, but monotypic stands uncommon. | |
Bromus hordeaceus | soft brome | 3Limited | B | C | A | 2.8 |
|
Grasslands, sagebrush, serpentine soils, many other habitats. Very widespread, but primarily in converted annual grasslands. | |
Bromus japonicus | Japanese brome, Japanese chess | 3Limited | B | C | B | 2.6 |
|
Great Basin grassland, valley and foothill grassland, pinon and juniper woodland, lower montane coniferous forest | |
Bromus madritensis ssp. rubens | red brome | 1High | A | B | A | 3.0 |
|
Scrub, grassland, desert washes, woodlands | |
Bromus tectorum | downy brome, cheatgrass | 1High | A | B | A | 3.1 |
|
Interior scrub, woodlands, grasslands, pinon/Joshua tree woodland, chaparral. | |
Buddleja davidii | butterflybush | 4Eval No List | D | B | D | 2.5 |
|
Not known to be invasive in CA, although it is a problem in Oregon. | |
Cakile maritima | European sea-rocket | 3Limited | C | B | B | 3.6 |
|
Coastal dunes. Widespread, but impacts appear to be minor. | |
Cardaria chalepensis | lens-podded white-top | 2Moderate | Alert | B | B | C | 3.2 |
|
Central Valley wetlands. Limited distribution in CA. May not be as invasive as C. draba. |
Cardaria draba | hoary cress | 2Moderate | B | B | B | 2.6 |
|
Riparian areas, marshes of central coast. More severe invasive in northern CA. | |
Cardaria pubescens | hairy whitetop | 3Limited | C | B | C | 2.5 |
|
Grasslands and meadows. Impacts unknown but may be significant in meadows of CaR. | |
Carduus acanthoides | plumeless thistle | 3Limited | B | C | C | 3.0 |
|
Valley and foothill grasslands. Distribution limited in CA, impacts higher locally. | |
Carduus nutans | musk thistle | 2Moderate | B | B | B | 3.1 |
|
Grasslands. More invasive in other western states. Limited distribution in CA. | |
Carduus pycnocephalus | Italian thistle | 2Moderate | B | B | A | 2.9 |
|
Forest, scrub, grasslands, woodland. Very widespread. Impacts may be variable regionally. | |
Carduus tenuiflorus | slenderflower thistle | 3Limited | C | C | B | 2.8 |
|
Valley and foothill grasslands. Limited distribution, Impacts appear to be minor. | |
Carpobrotus chilensis | sea-fig, iceplant | 2Moderate | B | B | A | 1.8 |
|
Coastal dunes, scrub, prairie. Little information on species, most inferred from C. edulis. | |
Carpobrotus edulis | Hottentot-fig, iceplant | 1High | A | B | A | 3.3 |
|
Coastal habitats, especially dunes | |
Carthamus lanatus | woolly distaff thistle | 2Moderate | Alert | A | B | C | 2.8 |
|
Grasslands. Expanding in coast ranges, may become more severe. Current distribution limited. |
Centaurea calcitrapa | purple starthistle | 2Moderate | B | B | B | 2.7 |
|
Grasslands. Impacts regionally variable. Distribution relatively limited. | |
Centaurea debeauxii | meadow knapweed | 2Moderate | Alert | B | B | C | 2.7 |
|
Grasslands. Spreading rapidly in NW CA, but distribution limited elsewhere. Little known of impacts. |
Centaurea diffusa | diffuse knapweed | 2Moderate | B | B | B | 3.3 |
|
Severe impacts in other western states. Limited distribution in CA with impacts higher in some locations. | |
Centaurea maculosa | spotted knapweed | 1High | A | B | B | 3.4 |
|
Riparian, grasslands, wet meadows, forests. More widely distributed in other western states. | |
Centaurea melitensis | Malta starthistle, tocalote | 2Moderate | B | B | B | 2.6 |
|
Grasslands, oak woodland; sometimes misidentified as C. solstitialis. Impacts vary regionally. | |
Centaurea solstitialis | yellow starthistle | 1High | A | B | A | 3.0 |
|
Grasslands, woodlands, occasionally riparian | |
Centaurea virgata ssp. squarrosa | squarrose knapweed | 2Moderate | B | B | B | 2.8 |
|
Scrub, grassland, pinyon-juniper woodland. Highly invasive in UT and other western states. Limited distribution in CA. | |
Cestrum parqui | willow jessamine | 4Eval No List | U | B | C | 2.0 |
|
Impacts unknown | |
Chondrilla juncea | rush skeletonweed | 2Moderate | B | B | B | 3.1 |
|
Grasslands. Very invasive in other western states, but currently limited in distribution in CA. | |
Chorispora tenella | blue mustard | 4Eval No List | U | C | C | 1.5 |
|
Impacts unknown | |
Chrysanthemum coronarium | crown daisy | 2Moderate | B | B | B | 2.0 |
|
Coastal prairie, dunes, and scrub. Impacts generally low to moderate, but can vary regionally. | |
Cirsium arvense | Canada thistle | 2Moderate | B | B | B | 2.8 |
|
Grasslands, riparian areas, forests. Severe impacts in other western states. Limited distribution in CA. | |
Cirsium vulgare | bull thistle | 2Moderate | B | B | B | 3.3 |
|
Riparian areas, marshes, meadows. Widespread, can be very problematic regionally. | |
Cistus ladanifer | gum rockrose | 4Eval No List | D | C | C | 3.3 |
|
Negligible known impacts in wildlands | |
Conicosia pugioniformis | narrowleaf iceplant | 3Limited | C | B | C | 2.1 |
|
Coastal dunes, scrub, grassland. Limited distribution. Impacts generally minor but can be higher locally. | |
Conium maculatum | poison-hemlock | 2Moderate | B | B | B | 2.8 |
|
Riparian woodland, grassland. Widespread in disturbed areas. Abiotic impacts unknown. Impacts can vary locally. | |
Convolvulus arvensis | field bindweed | 4Eval No List | C | B | B | 3.5 |
|
Only known as agricultural weed | |
Cordyline australis | giant dracaena, New Zealand cabbage tree | 3Limited | C | C | C | 2.0 |
|
Coniferous forest. Two reports of horticultural escape into wildlands. Appears best suited to moist, cool climates. | |
Cortaderia jubata | jubatagrass | 1High | A | A | A | 3.1 |
|
Many coastal and interior habitats | |
Cortaderia selloana | pampasgrass | 1High | A | A | B | 3.2 |
|
Coastal dunes, coastal scrub, Monterey pine, riparian, grasslands, wetlands, serpentine soils. Still spreading both coastal and inland. | |
Cotoneaster franchetii | orange cotoneaster | 2Moderate | B | A | B | 2.6 |
|
Coniferous forest. Limited distribution. Abiotic impacts largely unknown. | |
Cotoneaster lacteus | Parney's cotoneaster | 2Moderate | B | B | B | 2.1 |
|
Many coastal habitats, mainly a problem from SF Bay Area north along coast but also in San Diego County. Limited distribution. Abiotic impacts largely unknown. | |
Cotoneaster pannosus | silverleaf cotoneaster | 2Moderate | B | A | B | 2.5 |
|
Many coastal habitats, mainly a problem from SF Bay Area north along coast. Limited distribution. Abiotic impacts largely unknown. | |
Cotula coronopifolia | brassbuttons | 3Limited | C | C | B | 2.2 |
|
Salt and freshwater marshes. Impacts largely unknown, but appear to be minor. | |
Crataegus monogyna | hawthorn | 3Limited | C | B | C | 3.4 |
|
Riparian habitats, woodland. Limited distribution. Impacts appear to be minor. | |
Crocosmia x crocosmiiflora | montbretia | 3Limited | C | B | B | 2.6 |
|
Coastal scrub and prairie, north coast forests. Abiotic impacts unknown. Higher invasiveness in some areas. | |
Crupina vulgaris | common crupina, bearded creeper | 3Limited | B | C | B | 3.2 |
|
Forest, woodland, grassland. Distribution limited. More invasive in other western states. | |
Cupressus macrocarpa | Monterey cypress | 5Native | B | B | B | 2.3 |
|
Native to Monterey area. Invades coastal prairie, desert scrub, riparian areas. | |
Cynara cardunculus | artichoke thistle | 2Moderate | B | B | B | 4.0 |
|
Coastal grasslands. Impacts more severe in southern CA where monotypic stands are more common. | |
Cynodon dactylon | bermudagrass | 2Moderate | B | B | B | 3.3 |
|
Riparian scrub in southern CA. Common landscape weed, but can be very invasive in desert washes. | |
Cynoglossum officinale | houndstongue | 2Moderate | B | B | B | 2.5 |
|
Woodland, forest, interior dunes. Abiotic impacts unknown. Limited distribution. Can have impacts in other western states. | |
Cynosurus echinatus | hedgehog dogtailgrass | 2Moderate | B | B | A | 2.5 |
|
Oak woodland, grassland. Widespread, impacts vary regionally, but typically not in monotypic stands. | |
Cytisus scoparius | Scotch broom | 1High | A | B | A | 3.2 |
|
Coastal scrub, oak woodland, horticultural varieties may also be invasive. | |
Cytisus striatus | Portuguese broom | 2Moderate | B | B | B | 2.7 |
|
Coastal scrub, grasslands; often confused with C. scoparius. Limited distribution. | |
Dactylis glomerata | orchardgrass | 3Limited | C | B | B | 2.9 |
|
Grasslands, broadleaved forest, woodlands; common forage species. Impacts appear to be minor. | |
Daucus carota | wild carrot, Queen Anne's lace | 4Eval No List | D | C | B | 2.7 |
|
Very widespread, but primarily in disturbed sites, particularly roadsides | |
Delairea odorata | Cape-ivy, German-ivy | 1High | A | A | B | 3.1 |
|
Coastal, occasionally other riparian areas, common discard from gardens. | |
Descurainia sophia | flixweed, tansy mustard | 3Limited | C | B | B | 1.9 |
|
Scrub, grassland, woodland. Impacts appear to be minor, but locally more invasive in NE CA. | |
Digitalis purpurea | foxglove | 3Limited | C | B | B | 2.4 |
|
Forest, woodland. Widely escaped ornamental. Impacts largely unknown but appear to be minor. | |
Dimorphotheca sinuata | African daisy | 4Eval No List | D | C | B | 1.8 |
|
Impacts to abiotic processes and plant communities unknown | |
Dipsacus fullonum | common teasel | 2Moderate | B | B | B | 3.8 |
|
Grasslands, seep, riparian scrub. Impacts regionally variable, forms dense stands on occasion. | |
Dipsacus sativus | fuller's teasel | 2Moderate | B | B | B | 3.8 |
|
Grasslands, seep, bogs. Impacts regionally variable, forms dense stands on occasion. | |
Dittrichia graveolens | stinkwort | 2Moderate | Alert | B | A | C | 3.0 |
|
Grasslands, riparian scrub. Spreading rapidly, impacts may become more important in future. |
Echium candicans | pride-of-Madeira | 3Limited | C | B | B | 1.5 |
|
Little information on impacts. | |
Egeria densa | Brazilian egeria | 1High | A | A | B | 3.1 |
|
Streams, ponds, sloughs, lakes, Sacramento-San Joaquin Delta. | |
Ehrharta calycina | purple veldtgrass | 1High | A | A | B | 3.4 |
|
Sandy soils, especially dunes; rapidly spreading on central coast. | |
Ehrharta erecta | erect veldtgrass | 2Moderate | B | B | B | 2.2 |
|
Scrub, grasslands, woodland, forest. Spreading rapidly, impacts may become more important in future. | |
Ehrharta longiflora | long-flowered veldtgrass | 2Moderate | Alert | B | B | C | 2.8 |
|
Coastal scrub. Limited distribution, but spreading rapidly in southern CA. Impacts largely unknown. |
Eichhornia crassipes | water hyacinth | 1High | Alert | A | A | C | 3.2 |
|
Aquatic systems in Sacramento-San Joaquin Delta |
Elaeagnus angustifolia | Russian-olive | 2Moderate | B | A | B | 3.3 |
|
Interior riparian. Impacts more severe in other western states. Current distribution limited in CA. | |
Emex spinosa | spiny emex, devil's-thorn | 2Moderate | Alert | B | B | D | 1.6 |
|
Edges of beaches, other coastal habitats. Invasive in other states and countries. Spreading rapidly in southern CA. Impacts not well known. |
Erechtites glomerata, E. minima | Australian fireweed, Australian burnweed | 2Moderate | C | B | A | 3.2 |
|
Coastal woodland, scrub, forests. Widespread on coast, but impacts low overall. May vary locally. | |
Erigeron karvinskianus | Mexican daisy | 4Eval No List | U | B | C | 1.9 |
|
Impacts unknown, but appears to be expanding. May become more problematic in future | |
Erodium botrys | broadleaf filaree | 4Eval No List | D | C | A | 2.8 |
|
Present in wildlands but known impacts are negligible. Often transient. | |
Erodium brachycarpum | short-fruited filaree | 4Eval No List | C | C | A | 2.6 |
|
Present in wildlands but known impacts are negligible.Often transient. | |
Erodium cicutarium | redstem filaree | 3Limited | C | C | A | 3.1 |
|
Many habitats. Widespread. Impacts minor in wildlands. High-density populations transient. | |
Erodium moschatum | whitestem filaree | 4Eval No List | D | C | A | 2.7 |
|
Primarily an agricultural weed, little impact in wildlands. | |
Eucalyptus camaldulensis | red gum | 3Limited | C | C | C | 2.2 |
|
Mainly southern CA urban areas. Impacts, invasiveness and distribution all minor. | |
Eucalyptus globulus | Tasmanian blue gum | 2Moderate | B | B | B | 2.8 |
|
Riparian areas, coastal grasslands, scrub. Impacts can be much higher in coastal areas. | |
Euphorbia esula | leafy spurge | 1High | Alert | A | A | C | 3.5 |
|
Forests, woodlands, juniper forest. More widespread invasive in northern states. |
Euphorbia lathyris | caper spurge | 4Eval No List | D | C | B | 2.2 |
|
Abiotic impacts unknown | |
Euphorbia oblongata | oblong spurge | 3Limited | C | C | B | 2.0 |
|
Meadows, woodlands. Limited distribution. Impacts unknown. Locally in dense stands. | |
Euphorbia terracina | carnation spurge | 2Moderate | Alert | B | B | C | 1.7 |
|
Coastal scrub. Limited distribution. Spreading in southern CA. Impacts unknown. |
Festuca arundinacea | tall fescue | 2Moderate | B | B | A | 2.9 |
|
Coastal scrub, grasslands; common forage grass. Widespread, abiotic impacts unknown. | |
Ficus carica | edible fig | 2Moderate | B | A | B | 2.6 |
|
Riparian woodland. Can spread rapidly. Abiotic impacts unknown. Can be locally very problematic. | |
Foeniculum vulgare | fennel | 1High | A | B | A | 3.0 |
|
Grasslands, scrub. | |
Fraxinus uhdei | evergreen ash, shamel ash, tropical ash | 4Eval No List | U | B | D | 3.0 |
|
||
Fumaria officinalis | fumitory | 4Eval No List | D | C | D | 2.3 |
|
Abiotic impacts unknown | |
Genista monspessulana | French broom | 1High | A | A | B | 3.2 |
|
Coastal scrub, oak woodland, grasslands. Horticultural selections may also be invasive. | |
Geranium dissectum | cutleaf geranium | 2Moderate | C | B | A | 1.7 |
|
Numerous habitats but impacts appear minor. | |
Geranium molle | dovefoot geranium | 4Eval No List | D | B | A | 1.7 |
|
Present in wildlands, but known impacts are negligible | |
Geranium retrorsum | New Zealand geranium | 4Eval No List | D | B | B | 1.9 |
|
Present in wildlands, but known impacts are negligible | |
Geranium robertianum | herb-robert, Robert geranium | 4Eval No List | D | B | C | 2.8 |
|
Present in wildlands, but known impacts are negligible | |
Gleditsia triacanthos | honey locust | 4Eval No List | D | B | C | 3.3 |
|
Impacts unknown and distribution very limited | |
Glyceria declinata | waxy mannagrass | 2Moderate | B | B | B | 1.9 |
|
Vernal pools, moist grasslands. Often confused with native Glyceria. Impacts largely unknown, but may be significant in vernal pools. | |
Halogeton glomeratus | halogeton | 2Moderate | B | A | B | 3.0 |
|
Scrub, grasslands, pinyon-juniper woodland. Larger problem in NV. Monotypic stands are rare. | |
Hedera helix, H. canariensis | English ivy, Algerian ivy | 1High | A | A | A | 2.7 |
|
Coastal forests, riparian areas. Species combined due to genetics questions. | |
Helichrysum petiolare | licoriceplant | 3Limited | C | B | C | 2.0 |
|
North coastal scrub. Limited distribution. Impacts unknown, but can form dense stands. | |
Hirschfeldia incana | shortpod mustard, summer mustard | 2Moderate | B | B | A | 1.9 |
|
Scrub, grasslands, riparian areas. Impacts not well understood, but appear to be greater in southern CA. | |
Holcus lanatus | common velvet grass | 2Moderate | B | B | A | 2.9 |
|
Coastal grasslands, wetlands. Impacts can be more severe locally, especially in wetland areas. | |
Hordeum marinum, H. murinum | Mediterranean barley, hare barley, wall barley | 2Moderate | B | B | A | 2.8 |
|
Grasslands; H. marinum invades drier habitats, while H. murinum invades wetlands. Widespread, but generally do not form dominant stands. | |
Hydrilla verticillata | hydrilla | 1High | Alert | A | B | C | 3.2 |
|
Freshwater aquatic systems. The most important submerged aquatic invasive in southern states. |
Hypericum canariense | Canary Island hypericum | 2Moderate | Alert | B | B | C | 1.2 |
|
Coastal scrub, prairie. Impacts unknown, distribution limited. Spreading rapidly on central coast. |
Hypericum perforatum | common St. John's wort, klamathweed | 2Moderate | B | B | B | 3.7 |
|
Many northern CA habitats. Abiotic impacts low. Biological control agents have reduced overall impact. | |
Hypochaeris glabra | smooth catsear | 3Limited | C | B | B | 3.1 |
|
Scrub and woodlands. Widespread. Impacts appear to be minor. Some local variability. | |
Hypochaeris radicata | rough catsear, hairy dandelion | 2Moderate | C | B | A | 2.2 |
|
Coastal dunes, scrub, and prairie; woodland, forest. Widespread. Impacts unknown or appear to be minor. | |
Ilex aquifolium | English holly | 2Moderate | Alert | B | B | C | 2.7 |
|
North coast forests. Expanding range south from OR. |
Iris pseudacorus | yellowflag iris | 3Limited | C | B | C | 2.3 |
|
Riparian, wetland areas, esp. southern CA. Limited distribution. Abiotic impacts unknown. | |
Isatis tinctoria | dyer's woad | 2Moderate | B | B | A | 3.0 |
|
Great Basin scrub and grasslands, coniferous forest. More severe impacts in other western states, but can be locally very invasive in northern CA. | |
Kochia scoparia | kochia | 2Moderate | B | C | B | 3.2 |
|
Scrub, chaparral, grasslands | |
Lactuca serriola | prickly lettuce | 4Eval No List | D | B | B | 3.1 |
|
Primarily an agricultural and roadside weed | |
Lepidium latifolium | perennial pepperweed, tall whitetop | 1High | A | A | A | 3.1 |
|
Coastal and inland marshes, riparian areas, wetlands, grasslands; potential to invade montane wetlands. | |
Leptospermum laevigatum | Australian tea tree | 4Eval No List | D | C | D | 2.2 |
|
Very limited distribution. | |
Leucanthemum vulgare | ox-eye daisy | 2Moderate | B | B | B | 2.5 |
|
Montane meadows, coastal grasslands, coastal scrub. Expanding range, invasiveness varies locally. | |
Ligustrum lucidum | glossy privet | 4Eval No List | D | B | C | 3.1 |
|
May prove to be problematic in riparian areas. | |
Linaria genistifolia ssp. dalmatica | Dalmation toadflax | 2Moderate | B | B | B | 2.8 |
|
Grasslands, forest clearings. Limited distribution. More severe impacts in other western states. | |
Linaria vulgaris | yellow toadflax, butter and eggs | 2Moderate | B | B | B | 2.3 |
|
valley and foothill grassland, Great Basin grassland, riparian woodland, lower montane coniferous forest, upper montane coniferous forest | |
Lobularia maritima | sweet alyssum | 3Limited | C | B | B | 2.4 |
|
Coastal dune, coastal scrub, coastal prairie, riparian. | |
Lolium multiflorum | Italian ryegrass | 2Moderate | A | B | A | 2.6 |
|
Grasslands, oak woodland, pinyon-juniper woodland; widely used for post-fire erosion control. Widespread. Impacts can vary with region. | |
Lotus corniculatus | birdsfoot trefoil | 4Eval No List | D | B | B | 2.8 |
|
Primarily a turf or agricultural weed in CA | |
Ludwigia hexapetala | Uruguay water-primrose | 1High | Alert | A | B | C | 2.6 |
|
Freshwater aquatic systems. Clarification needed on taxonomic identification. |
Ludwigia peploides ssp. montevidensis | creeping water-primrose | 1High | A | B | B | 2.5 |
|
Freshwater aquatic systems. Clarification needed on taxonomic identification. | |
Lupinus arboreus | yellow bush lupine | 5Native | B | B | B | 3.5 |
|
Invasive in NW coastal dunes. | |
Lythrum hyssopifolium | hyssop loosestrife | 3Limited | C | B | B | 3.0 |
|
Grasslands, wetlands, vernal pools. Widespread. Impacts unknown, but appear to be minor. | |
Lythrum salicaria | purple loosestrife | 1High | A | A | B | 3.8 |
|
Wetlands, marshes, riparian areas | |
Malephora crocea | coppery mesembryanthemum | 4Eval No List | D | C | C | 2.0 |
|
A problem on southern CA islands, but statewide impacts are low | |
Marrubium vulgare | white horehound | 3Limited | C | C | B | 2.8 |
|
Grasslands scrub, riparian areas. Widespread. Rarely in dense stands. Impacts relatively minor. | |
Maytenus boaria | mayten | 4Eval No List | D | C | D | 2.4 |
|
Infestation on Angel Island, San Francisco Bay | |
Medicago polymorpha | California burclover | 3Limited | C | C | A | 2.8 |
|
Grasslands. Widespread weed of agriculture and disturbed areas. Impacts in wildlands minor. | |
Melilotus officinalis | yellow sweetclover | 4Eval No List | D | C | C | 3.3 |
|
Present in human-disturbed habitats only | |
Mentha pulegium | pennyroyal | 2Moderate | C | A | A | 2.7 |
|
Vernal pools, wetlands. Poisonous to livestock. Spreading rapidly. Impacts largely unknown. | |
Mesembryanthemum crystallinum | crystalline iceplant | 2Moderate | Alert | B | B | C | 3.7 |
|
Coastal bluffs, dunes, scrubs, grasslands. Limited distribution. Locally problematic, especially in southern CA. |
Myoporum laetum | myoporum | 2Moderate | B | B | B | 2.6 |
|
Coastal habitats, riparian areas; mostly along the southern coast. Abiotic impacts unknown. | |
Myosotis latifolia | common forget-me-not | 3Limited | C | B | B | 2.2 |
|
Coniferous forest, riparian. Little information on impacts. | |
Myriophyllum aquaticum | parrotfeather | 1High | Alert | A | B | C | 2.8 |
|
Freshwater aquatic systems |
Myriophyllum spicatum | Eurasian watermilfoil | 1High | A | A | B | 2.8 |
|
Freshwater aquatic systems | |
Nerium oleander | oleander | 4Eval No List | D | B | D | 2.6 |
|
Not known to be invasive, although reported from riparian areas in Central Valley and San Bernardino Mtns | |
Nicotiana glauca | tree tobacco | 2Moderate | B | B | B | 2.5 |
|
Coastal scrub, grasslands, riparian woodland. Abiotic impacts unknown. Impacts vary locally. Rarely in dense stands. | |
Nothoscordum gracile | false garlic | 4Eval No List | D | B | D | 2.1 |
|
Mainly an urban garden weed. | |
Nymphaea odorata | fragrant waterlily | 4Eval No List | D | B | C | 2.3 |
|
Present only at one site. | |
Olea europaea | olive | 3Limited | C | B | B | 2.5 |
|
A problem in Australia. Currently a rare escape in CA but is of concern due to the possibility of spread from planted groves. | |
Ononis alopecuroides | foxtail restharrow | 3Limited | C | B | C | 2.2 |
|
Grasslands, oak woodland. Highly invasive. Impacts unknown. Nearly eradicated. | |
Onopordum acanthium | Scotch thistle | 1High | B | B | B | 2.9 |
|
Wet meadows, sage brush, riparian areas | |
Oxalis corniculata | creeping woodsorrel | 4Eval No List | D | C | C | 2.2 |
|
Primarily a turf weed in CA | |
Oxalis pes-caprae | Bermuda buttercup, buttercup oxalis, yellow oxalis | 2Moderate | B | B | B | 2.9 |
|
Coastal dunes, scrub, oak woodland. Impacts in coastal areas may prove more severe in time. | |
Parentucellia viscosa | yellow glandweed, sticky parentucellia | 3Limited | C | B | B | 2.5 |
|
Coastal prairie, grassland, and dunes. Impacts unknown, but can be locally significant. | |
Parkinsonia aculeata | Mexican Palo Verde | 4Eval No List | D | B | D | 2.2 |
|
Has not escaped into wildland enough to cause impacts. | |
Pennisetum clandestinum | kikuyugrass | 3Limited | C | C | B | 2.3 |
|
Present at low levels in numerous wildland habitats. Impacts unknown. Common turf weed. | |
Pennisetum setaceum | crimson fountaingrass | 2Moderate | B | B | B | 2.9 |
|
Coastal dunes and scrub, chaparral, grasslands. Some horticultural cultivars sterile. Very invasive in Hawaii. | |
Pennisetum villosum | feathertop | 4Eval No List | U | B | C | 2.4 |
|
||
Phalaris aquatica | hardinggrass | 2Moderate | B | B | B | 2.6 |
|
Coastal sites, especially moist soils. Limited distribution. Can be highly invasive locally. | |
Phoenix canariensis | Canary Island date palm | 3Limited | C | B | D | 2.3 |
|
Desert washes; agricultural crop plant. Limited distribution in southern CA. Impacts can be higher locally. | |
Phragmites australis | common reed | 5Native | B | B | B | 2.5 |
|
Genetic issues make it unclear which strains are native to CA. | |
Phytolacca americana | common pokeweed | 3Limited | C | B | C | 2.8 |
|
riparian forest, riparian woodland | |
Picris echioides | bristly oxtongue | 3Limited | C | B | B | 2.4 |
|
Coastal prairie, scrub, riparian woodland. Widespread locally. Abiotic impacts unknown. | |
Pinus radiata cultivars | Monterey pine | 5Native | B | B | B | 2.6 |
|
Five populations native to CA. Invades coastal scrub and prairie, chaparral. | |
Piptatherum miliaceum | smilograss | 3Limited | C | B | B | 2.4 |
|
Coastal dunes, scrub, riparian, grassland. Expanding range. Impacts largely unknown. | |
Pistachia chinensis | Chinese pistache | 4Eval No List | U | C | D | 0.9 |
|
Impacts unknown | |
Pittosporum undulatum | Victorian box | 4Eval No List | D | C | D | 2.7 |
|
Infestations in California are small. More problematic on north coast | |
Plantago coronopus | cutleaf plantain | 4Eval No List | U | C | B | 1.7 |
|
Impacts unknown. Common on north coast | |
Plantago lanceolata | buckhorn plantain, English plantain | 3Limited | C | C | B | 2.1 |
|
Many habitats. Turf weed primarily. Low density and impact in wildlands. | |
Poa pratensis | Kentucky bluegrass | 3Limited | C | B | B | 2.7 |
|
Grasslands scrub, riparian areas. Widespread turf plant. Abiotic impacts unknown. | |
Polygonum cuspidatum | Japanese knotweed | 2Moderate | Alert | B | B | D | 2.7 |
|
Riparian areas, wetlands, forest edges. More severe impacts in NW wetlands. Distribution limited in CA. |
Polygonum sachalinense | Sakhalin knotweed | 2Moderate | Alert | B | B | D | 2.5 |
|
Riparian areas. More severe impacts in NW wetlands. Distribution limited in CA. |
Polypogon monspeliensis and subspp. | rabbitfoot polypogon, annual beardgrass | 3Limited | C | C | B | 2.3 |
|
Margins of ponds and streams, seasonally wet places, edge of coastal dunes. Widespread. Impacts appear to be minor. | |
Potamogeton crispus | curlyleaf pondweed | 2Moderate | B | B | B | 3.2 |
|
Freshwater aquatic systems. Can be very invasive locally. | |
Prunus cerasifera | cherry plum | 3Limited | C | B | B | 1.8 |
|
Riparian habitats, chaparral, woodland. Limited distribution. Abiotic impacts unknown. | |
Pyracantha angustifolia, P. crenulata, P. coccinea | pyracantha, firethorn | 3Limited | C | B | B | 2.8 |
|
Coastal scrub and prairie, riparian areas. Horticultural escape. Impacts unknown or minor. | |
Ranunculus repens | creeping buttercup | 3Limited | C | C | B | 2.9 |
|
Riparian areas, coniferous forest. Impacts appear to be minor to negligible in most areas. | |
Raphanus sativus | radish | 3Limited | C | C | B | 2.5 |
|
Present at low levels in numerous habitats. Widespread in disturbed sites. | |
Retama monosperma | bridal broom | 2Moderate | Alert | B | B | C | 1.8 |
|
Coastal scrub. Can spread rapidly but largely if uncontrolled. Limited distribution in CA. |
Ricinus communis | castorbean | 3Limited | C | B | B | 2.5 |
|
Coastal scrub and prairie, riparian areas. Widespread in southern CA. Impacts locally variable. | |
Robinia pseudoacacia | black locust | 3Limited | C | B | B | 2.8 |
|
Riparian areas, canyons. Severe impacts in southern states. Impacts minor in CA. | |
Rubus armeniacus | Himalaya blackberry | 1High | A | A | A | 3.0 |
|
Riparian areas, marshes, oak woodlands | |
Rumex acetosella | red sorrel, sheep sorrel | 2Moderate | B | B | A | 2.3 |
|
Many habitats, riparian areas, forest, wetlands. Widespread. Abiotic impacts unknown. Impacts can vary locally. | |
Rumex crispus | curly dock | 3Limited | C | C | A | 2.7 |
|
Grasslands, vernal pool, meadows, riparian. Widespread. Impacts appear to be minor. | |
Saccharum ravennae | ravennagrass | 2Moderate | Alert | B | A | C |
|
riparian scrub, marsh and swamp | |
Salsola paulsenii | barbwire Russian-thistle | 3Limited | C | C | C | 2.9 |
|
Desert and Great Basin scrub. Limited distribution. Impacts in desert appear to be minor. | |
Salsola soda | oppositeleaf Russian thistle | 2Moderate | B | B | B | 2.8 |
|
marine systems, estuaries, vernal pool, marsh and swamp | |
Salsola tragus | Russian-thistle | 3Limited | C | B | B | 2.8 |
|
Desert dunes and scrub, alkali playa. Widespread. Impacts minor in wildlands. | |
Salvia aethiopis | Mediterranean sage | 3Limited | C | B | B | 2.5 |
|
Sagebrush, juniper, bunchgrass. Distribution limited. Impacts minor but can be locally higher. | |
Salvinia molesta | giant salvinia | 1High | Alert | A | A | C | 2.9 |
|
Freshwater aquatic systems. Population in San Diego River was eradicated. |
Sapium sebiferum | Chinese tallowtree | 2Moderate | Alert | B | B | C | 3.2 |
|
Riparian areas. Impacts severe in southeast US. Limited distribution in California, but spreading rapidly regionally. |
Saponaria officinalis | bouncingbet | 3Limited | C | B | C | 2.5 |
|
Riparian scrub and woodland. Impacts unknown or minor, but appear to be locally variable. | |
Schinus molle | Peruvian peppertree | 3Limited | C | B | B | 2.5 |
|
Riparian. Limited distribution. Impacts largely unknown in CA. | |
Schinus terebinthifolius | Brazilian peppertree | 3Limited | C | B | C | 2.6 |
|
Riparian. Very invasive in tropics. Abiotic impacts unknown, but appear significant locally. | |
Schismus arabicus, Schismus barbatus | mediterraneangrass | 3Limited | B | C | A | 2.3 |
|
Scrub, thorn woodland. Widespread in deserts. Impacts can be more important locally. | |
Senecio jacobaea | tansy ragwort | 3Limited | C | B | B | 2.8 |
|
Grasslands, riparian. Impacts generally minor. Can be locally important in NW CA. | |
Sesbania punicea | red sesbania, scarlet wisteria | 1High | Alert | A | B | C | 3.2 |
|
Riparian areas |
Silybum marianum | blessed milkthistle | 3Limited | C | C | A | 3.5 |
|
Grasslands, riparian. Widespread, primarily in disturbed areas Impacts can be higher locally | |
Sinapis arvensis | wild mustard, charlock | 3Limited | C | C | C | 2.9 |
|
Grasslands. Primarily in disturbed sites. Impacts minor or unknown in wildlands. | |
Sisymbrium irio | London rocket | 2Moderate | B | B | A | 1.9 |
|
Scrub, grasslands. Widespread. Primarily in disturbed sites. Impacts vary locally. | |
Solanum elaeagnifolium | silverleaf nightshade | 4Eval No List | D | B | C | 2.8 |
|
Primarily agricultural weed, but escaping to wildlands in other countries. May prove to be more important in future. | |
Sonchus asper | spiny sowthistle | 4Eval No List | D | B | B | 3.1 |
|
Primarily an agricultural weed | |
Spartina alterniflora (and S. alterniflora x foliosa hybrids) | smooth cordgrass and hybrids, Atlantic cordgrass | 1High | Alert | A | A | C | 3.5 |
|
San Francisco Bay salt marshes and mudflats. Hybridizes with native S. foliosa. |
Spartina anglica | common cordgrass | 2Moderate | Alert | B | B | D | 3.4 |
|
San Francisco Bay salt marshes. Very severe impact in other countries. Limited distribution in CA. |
Spartina densiflora | dense-flowered cordgrass | 1High | Alert | A | B | D | 3.3 |
|
San Francisco and Humboldt Bay salt marshes |
Spartina patens | saltmeadow cord grass | 3Limited | C | C | D | 2.9 |
|
San Francisco Bay salt marshes. Very limited distribution. Impacts currently minor in CA, but high in other countries. | |
Spartium junceum | Spanish broom | 1High | A | B | B | 3.2 |
|
Coastal scrub, grasslands, wetlands, oak woodland, forests | |
Stipa capensis | Mediterranean steppegrass,twisted-awned speargrass | 2Moderate | Alert | B | B | D | 1.9 |
|
Desert scrub; first recorded in CA 1995. Limited distribution, but spreading rapidly in CA deserts. |
Taeniatherum caput-medusae | medusahead | 1High | A | A | A | 3.4 |
|
Grasslands, scrub, woodland | |
Tamarix aphylla | athel tamarisk | 3Limited | C | B | B | 3.5 |
|
Desert washes, riparian areas. Limited distribution. Impacts minor, but can be locally higher. | |
Tamarix parviflora | smallflower tamarisk | 1High | A | A | B | 3.1 |
|
Riparian areas, desert washes, coastal scrub | |
Tamarix ramosissima | saltcedar, tamarisk | 1High | A | A | A | 3.3 |
|
Desert washes, riparian areas, seeps and springs | |
Tanacetum vulgare | common tansy | 2Moderate | B | B | B | 2.3 |
|
Riparian areas, forest. Limited distribution. Severe problem in other western states. | |
Taraxacum officinale | common dandelion | 4Eval No List | D | B | B | 2.8 |
|
Primarily a turf weed in CA | |
Torilis arvensis | hedgeparsley | 2Moderate | C | B | B | 2.3 |
|
Expanding range. Appear to have only moderate ecological impacts. | |
Tragopogon dubius | yellow salsify | 4Eval No List | D | C | B | 3.2 |
|
Generally a minor component of disturbed areas. | |
Trifolium hirtum | rose clover | 2Moderate | C | B | B | 2.8 |
|
Grasslands, oak woodland. Widely planted in CA. Impacts relatively minor in most areas. | |
Tropaeolum majus | garden nasturtium | 4Eval No List | D | C | C | 1.4 |
|
Impacts on abiotic processes and native plants unknown | |
Ulex europaeus | gorse | 1High | A | B | B | 2.9 |
|
Scrub, woodland, forest, coastal grassland | |
Ulmus pumila | Siberian elm | 4Eval No List | D | B | B | 2.5 |
|
Impacts unknown | |
Undaria pinnatifida | wakame | 3Limited | C | B | C | 3.3 |
|
Alga of estuaries. First recorded in CA in 2000. Impacts unknown, but do not appear to be significant | |
Verbascum thapsus | common mullein,woolly mullein | 3Limited | C | B | B | 3.8 |
|
Meadows, riparian, sagebrush, pinyon-juniper woodlands. Widespread. Impacts minor. | |
Verbena bonariensis, Verbena litoralis | tall vervain, seashore vervain | 4Eval No List | D | B | C | 2.1 |
|
Often in disturbed areas of irrigation canals | |
Vicia villosa | hairy vetch | 4Eval No List | D | C | B | 2.8 |
|
Primarily an agricultural weed, Widespread but impacts minor in wildlands. | |
Vinca major | big periwinkle | 2Moderate | B | B | B | 2.8 |
|
Riparian, oak woodlands, coastal scrub. Distribution currently limited but spreading in riparian areas. Impacts can be higher locally. | |
Vulpia bromoides | squirreltail fescue | 4Eval No List | D | C | B | 2.9 |
|
Less common than V. myuros | |
Vulpia myuros | rattail fescue | 2Moderate | B | B | A | 3.0 |
|
Coastal sage scrub, chaparral. Widespread. Rarely forms monotypic stands, but locally problematic | |
Washingtonia robusta | Mexican fan palm | 2Moderate | Alert | B | B | C | 2.7 |
|
Desert washes. Limited distribution but spreading in southern CA. Impacts can be higher locally. |
Watsonia meriana | bulbil watsonia | 3Limited | C | B | C | 2.3 |
|
Coastal prairie, coniferous forest. Abiotic impacts unknown, but may be locally dense. | |
Zantedeschia aethiopica | calla lily | 3Limited | C | B | C | 2.1 |
|
Coastal prairie, wetlands. Impacts high in other countries and local impacts may be high in CA. |
Column heading abbreviations:
Imp. = ImpactInv. = Invasiveness
Dis. = Distribution
Doc. = Documentation Level (Documentation level averaged)
Scores:
A = SevereB = Moderate
C = Limited
D = None
U = Unknown
Nomenclature:
Scientific names are based on The Jepson Manual.For each species, the first common name is based on the Weed Science Society of America's "Composite List of Weeds", followed by other names used in California.
Citation:
Cal-IPC. 2006. California Invasive Plant Inventory. Cal-IPC Publication 2006-02. California Invasive Plant Council: Berkeley, CA.[ top of page ]