California Invasive Plant Inventory Database

Before looking at this database, please read the information on the Invasive Plant Inventory, including how plants were listed and what the ratings mean.

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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.

• CA Floristic Province (CA-FP)
  • Cascade Range (CaR)
  • Central West (CW)
  • Great Valley (GV)
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  • Sierra Nevada (SN)
  • Southwest (SW)

• Great Basin Province (GB)
  • Modoc Plateau (MP)
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• Desert Province (D)
  • Mojave Desert (DMoj)
  • Sonoran Desert (DSon)

• Plants invasive in all provinces (All CA)

     > See map of regions

     > See abbreviation and scores key

     > Read how the Inventory was compiled.

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	·CW ·NW ·SW	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	·CW ·NW ·SW	Coniferous forest, chaparral, woodland, riparian. Impacts are low in most areas.
Acroptilon repens	Russian knapweed	2Moderate		B	B	B	3.2	·CA-FP ·GB	Scrub, grasslands, riparian, pinyon-juniper woodland, forest. Severe impacts in other western states. Spreading in many areas of CA.
Agrostis avenacea	Pacific bentgrass	3Limited		C	C	C	2.4	·CW ·GV ·NW ·SN ·SW	Vernal pools, coastal prairie, meadows, grasslands. Impacts are low in most areas.
Agrostis stolonifera	creeping bentgrass	3Limited		C	B	C	1.9	·CW ·GV ·NW ·SN ·SW	Wetlands, riparian; grown for domestic forage. Limited distribution and impacts unknown.
Ailanthus altissima	tree-of-heaven	2Moderate		B	B	B	3.0	·CA-FP ·GB	Riparian areas, grasslands, oak woodland. Impacts highest in riparian areas.
Aira caryophyllea	silver hairgrass	4Eval No List		D	C	A	2.6	·CA-FP	Widespread in grasslands, but impacts appear negligible.
Aira praecox	European hairgrass	4Eval No List		D	C	C	2.8	·NW	Appears to be spreading locally, but impacts unknown.
Allium triquetrum	three-cornered leek	4Eval No List		U	C	C	1.6	·CW ·NW	Impacts unknown.
Ammophila arenaria	European beachgrass	1High		A	B	B	3.2	·CW ·NW ·SW	Coastal dunes
Anthemis cotula	mayweed chamomile, dog fennel	4Eval No List		D	B	B	2.4	·CW ·GV ·NW ·SN ·SW	Abiotic and wildife impacts unknown
Anthoxanthum odoratum	sweet vernalgrass	2Moderate		B	B	B	2.7	·CW ·NW ·SN	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	·CW ·NW	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	·CW ·NW ·SW	Coastal prairie; only propagates vegetatively. More competitive than fertile form, but limited distribution.
Arundo donax	giant reed	1High		A	B	A	2.8	·CW ·GV ·NW ·SN ·SW ·D	Riparian areas, commercially grown for musical instrument reeds, structural material, etc.
Atriplex semibaccata	Australian saltbush	2Moderate		B	B	B	2.9	·All CA	Coastal grasslands, scrub, upper salt marsh. Limited distribution, but can be very invasive regionally.
Bassia hyssopifolia	fivehook bassia	3Limited		C	C	B	2.7	·All CA	Alkaline habitats. Weed of agriculture or disturbed sites. Impacts minor in wildlands.
Bellardia trixago	bellardia	3Limited		C	C	C	1.9	·CW ·NW	Grasslands, including serpentine. Impacts and invasiveness appear to be minor.
Bellis perennis	English daisy	4Eval No List		D	C	C	2.8	·CW ·NW ·SW	Present along trails, not known to spread into undisturbed areas
Brassica nigra	black mustard	2Moderate		B	B	A	2.0	·CA-FP	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	·CA-FP ·SNE	Coastal scrub, grasslands meadows, riparian. Primarily in disturbed areas, Impacts appear to be minor or unknown in wildlands.
Briza maxima	big quackingrass, rattlesnakegrass	3Limited		B	C	B	2.3	·CW ·NW ·SN ·SW	Grasslands. Widespread in coast range. Impacts generally minor, but locally can be higher.
Bromus diandrus	ripgut brome	2Moderate		B	B	A	3.3	·All CA	Dunes, scrub, grassland, woodland, forest. Very widespread, but monotypic stands uncommon.
Bromus hordeaceus	soft brome	3Limited		B	C	A	2.8	·All CA	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	·CA-FP ·GB ·D	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	·All CA	Scrub, grassland, desert washes, woodlands
Buddleja davidii	butterflybush	4Eval No List		D	B	D	2.5	·CW ·NW	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	·CW ·NW ·SW	Coastal dunes. Widespread, but impacts appear to be minor.
Cardaria chalepensis	lens-podded white-top	2Moderate	Alert	B	B	C	3.2	·CA-FP ·GB	Central Valley wetlands. Limited distribution in CA. May not be as invasive as C. draba.
Carduus acanthoides	plumeless thistle	3Limited		B	C	C	3.0	·CW ·NW ·SN ·MP	Valley and foothill grasslands. Distribution limited in CA, impacts higher locally.
Carduus nutans	musk thistle	2Moderate		B	B	B	3.1	·CaR ·NW ·SN ·MP	Grasslands. More invasive in other western states. Limited distribution in CA.
Carduus pycnocephalus	Italian thistle	2Moderate		B	B	A	2.9	·CW ·GV ·NW ·SN ·SW ·DMoj	Forest, scrub, grasslands, woodland. Very widespread. Impacts may be variable regionally.
Carduus tenuiflorus	slenderflower thistle	3Limited		C	C	B	2.8	·CW ·NW ·SN ·SW	Valley and foothill grasslands. Limited distribution, Impacts appear to be minor.
Carpobrotus chilensis	sea-fig, iceplant	2Moderate		B	B	A	1.8	·CW ·NW ·SW	Coastal dunes, scrub, prairie. Little information on species, most inferred from C. edulis.
Carpobrotus edulis	Hottentot-fig, iceplant	1High		A	B	A	3.3	·CW ·NW ·SW	Coastal habitats, especially dunes
Carthamus lanatus	woolly distaff thistle	2Moderate	Alert	A	B	C	2.8	·CW ·NW ·SN	Grasslands. Expanding in coast ranges, may become more severe. Current distribution limited.
Centaurea calcitrapa	purple starthistle	2Moderate		B	B	B	2.7	·CW ·GV ·NW ·SN ·SW ·MP	Grasslands. Impacts regionally variable. Distribution relatively limited.
Centaurea debeauxii	meadow knapweed	2Moderate	Alert	B	B	C	2.7	·CW ·NW	Grasslands. Spreading rapidly in NW CA, but distribution limited elsewhere. Little known of impacts.
Centaurea diffusa	diffuse knapweed	2Moderate		B	B	B	3.3	·CaR ·CW ·NW ·SN ·SW ·GB	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	·CA-FP ·GB	Riparian, grasslands, wet meadows, forests. More widely distributed in other western states.
Centaurea melitensis	Malta starthistle, tocalote	2Moderate		B	B	B	2.6	·CaR ·NW ·SN ·D	Grasslands, oak woodland; sometimes misidentified as C. solstitialis. Impacts vary regionally.
Centaurea solstitialis	yellow starthistle	1High		A	B	A	3.0	·CA-FP	Grasslands, woodlands, occasionally riparian
Centaurea virgata ssp. squarrosa	squarrose knapweed	2Moderate		B	B	B	2.8	·CaR ·NW ·MP	Scrub, grassland, pinyon-juniper woodland. Highly invasive in UT and other western states. Limited distribution in CA.
Chondrilla juncea	rush skeletonweed	2Moderate		B	B	B	3.1	·CaR ·CW ·GV ·NW ·SN	Grasslands. Very invasive in other western states, but currently limited in distribution in CA.
Cirsium arvense	Canada thistle	2Moderate		B	B	B	2.8	·CA-FP ·DMoj	Grasslands, riparian areas, forests. Severe impacts in other western states. Limited distribution in CA.
Cirsium vulgare	bull thistle	2Moderate		B	B	B	3.3	·CA-FP ·GB	Riparian areas, marshes, meadows. Widespread, can be very problematic regionally.
Conium maculatum	poison-hemlock	2Moderate		B	B	B	2.8	·CA-FP	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	·All CA	Only known as agricultural weed
Cordyline australis	giant dracaena, New Zealand cabbage tree	3Limited		C	C	C	2.0	·CW ·NW	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	·CW ·NW ·SN ·SW	Many coastal and interior habitats
Cortaderia selloana	pampasgrass	1High		A	A	B	3.2	·CaR ·CW ·NW ·SN ·SW ·DMoj	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	·CW ·NW	Coniferous forest. Limited distribution. Abiotic impacts largely unknown.
Cotoneaster lacteus	Parney's cotoneaster	2Moderate		B	B	B	2.1	·CW ·NW ·SW	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	·CW ·NW ·SW	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	·CW ·NW ·SW	Salt and freshwater marshes. Impacts largely unknown, but appear to be minor.
Crataegus monogyna	hawthorn	3Limited		C	B	C	3.4	·CW ·NW	Riparian habitats, woodland. Limited distribution. Impacts appear to be minor.
Crocosmia x crocosmiiflora	montbretia	3Limited		C	B	B	2.6	·CW ·NW ·SW	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	·NW ·MP	Forest, woodland, grassland. Distribution limited. More invasive in other western states.
Cynodon dactylon	bermudagrass	2Moderate		B	B	B	3.3	·CA-FP ·D	Riparian scrub in southern CA. Common landscape weed, but can be very invasive in desert washes.
Cynosurus echinatus	hedgehog dogtailgrass	2Moderate		B	B	A	2.5	·CW ·GV ·NW ·SN ·SW	Oak woodland, grassland. Widespread, impacts vary regionally, but typically not in monotypic stands.
Cytisus scoparius	Scotch broom	1High		A	B	A	3.2	·CA-FP	Coastal scrub, oak woodland, horticultural varieties may also be invasive.
Cytisus striatus	Portuguese broom	2Moderate		B	B	B	2.7	·CW ·NW ·SW	Coastal scrub, grasslands; often confused with C. scoparius. Limited distribution.
Dactylis glomerata	orchardgrass	3Limited		C	B	B	2.9	·CA-FP ·GB	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	·All CA	Very widespread, but primarily in disturbed sites, particularly roadsides
Delairea odorata	Cape-ivy, German-ivy	1High		A	A	B	3.1	·CaR ·CW ·NW ·SW	Coastal, occasionally other riparian areas, common discard from gardens.
Descurainia sophia	flixweed, tansy mustard	3Limited		C	B	B	1.9	·All CA	Scrub, grassland, woodland. Impacts appear to be minor, but locally more invasive in NE CA.
Digitalis purpurea	foxglove	3Limited		C	B	B	2.4	·CW ·NW ·SN ·SW	Forest, woodland. Widely escaped ornamental. Impacts largely unknown but appear to be minor.
Dipsacus fullonum	common teasel	2Moderate		B	B	B	3.8	·CW ·NW ·SN ·SW	Grasslands, seep, riparian scrub. Impacts regionally variable, forms dense stands on occasion.
Dipsacus sativus	fuller's teasel	2Moderate		B	B	B	3.8	·CW ·NW ·SW	Grasslands, seep, bogs. Impacts regionally variable, forms dense stands on occasion.
Dittrichia graveolens	stinkwort	2Moderate	Alert	B	A	C	3.0	·CW ·GV ·NW ·SN ·SW	Grasslands, riparian scrub. Spreading rapidly, impacts may become more important in future.
Echium candicans	pride-of-Madeira	3Limited		C	B	B	1.5	·CW ·NW ·SW	Little information on impacts.
Erechtites glomerata, E. minima	Australian fireweed, Australian burnweed	2Moderate		C	B	A	3.2	·CW ·NW ·SW	Coastal woodland, scrub, forests. Widespread on coast, but impacts low overall. May vary locally.
Erodium botrys	broadleaf filaree	4Eval No List		D	C	A	2.8	·CA-FP	Present in wildlands but known impacts are negligible. Often transient.
Erodium brachycarpum	short-fruited filaree	4Eval No List		C	C	A	2.6	·CA-FP	Present in wildlands but known impacts are negligible.Often transient.
Erodium cicutarium	redstem filaree	3Limited		C	C	A	3.1	·All CA	Many habitats. Widespread. Impacts minor in wildlands. High-density populations transient.
Erodium moschatum	whitestem filaree	4Eval No List		D	C	A	2.7	·CA-FP	Primarily an agricultural weed, little impact in wildlands.
Eucalyptus camaldulensis	red gum	3Limited		C	C	C	2.2	·CW ·GV ·NW ·SW	Mainly southern CA urban areas. Impacts, invasiveness and distribution all minor.
Eucalyptus globulus	Tasmanian blue gum	2Moderate		B	B	B	2.8	·CW ·GV ·NW ·SW	Riparian areas, coastal grasslands, scrub. Impacts can be much higher in coastal areas.
Euphorbia esula	leafy spurge	1High	Alert	A	A	C	3.5	·CaR ·NW ·SW ·MP	Forests, woodlands, juniper forest. More widespread invasive in northern states.
Euphorbia lathyris	caper spurge	4Eval No List		D	C	B	2.2	·CW ·GV ·NW ·SW	Abiotic impacts unknown
Euphorbia oblongata	oblong spurge	3Limited		C	C	B	2.0	·CaR ·CW ·GV ·NW ·SN	Meadows, woodlands. Limited distribution. Impacts unknown. Locally in dense stands.
Festuca arundinacea	tall fescue	2Moderate		B	B	A	2.9	·CA-FP	Coastal scrub, grasslands; common forage grass. Widespread, abiotic impacts unknown.
Foeniculum vulgare	fennel	1High		A	B	A	3.0	·CA-FP	Grasslands, scrub.
Genista monspessulana	French broom	1High		A	A	B	3.2	·CaR ·CW ·NW ·SN ·SW	Coastal scrub, oak woodland, grasslands. Horticultural selections may also be invasive.
Geranium dissectum	cutleaf geranium	2Moderate		C	B	A	1.7	·CA-FP	Numerous habitats but impacts appear minor.
Geranium molle	dovefoot geranium	4Eval No List		D	B	A	1.7	·CA-FP	Present in wildlands, but known impacts are negligible
Geranium retrorsum	New Zealand geranium	4Eval No List		D	B	B	1.9	·CW ·NW ·SN ·SW	Present in wildlands, but known impacts are negligible
Hedera helix, H. canariensis	English ivy, Algerian ivy	1High		A	A	A	2.7	·CA-FP	Coastal forests, riparian areas. Species combined due to genetics questions.
Helichrysum petiolare	licoriceplant	3Limited		C	B	C	2.0	·CW ·NW ·SW	North coastal scrub. Limited distribution. Impacts unknown, but can form dense stands.
Hirschfeldia incana	shortpod mustard, summer mustard	2Moderate		B	B	A	1.9	·CW ·GV ·NW ·SN ·SW ·DMoj	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	·CA-FP ·GB ·DMoj	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	·All CA	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	·GV ·NW ·SN ·SW ·D	Freshwater aquatic systems. The most important submerged aquatic invasive in southern states.
Hypericum perforatum	common St. John's wort, klamathweed	2Moderate		B	B	B	3.7	·CW ·GV ·NW ·SW	Many northern CA habitats. Abiotic impacts low. Biological control agents have reduced overall impact.
Hypochaeris glabra	smooth catsear	3Limited		C	B	B	3.1	·CA-FP	Scrub and woodlands. Widespread. Impacts appear to be minor. Some local variability.
Hypochaeris radicata	rough catsear, hairy dandelion	2Moderate		C	B	A	2.2	·CA-FP	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	·CW ·NW	North coast forests. Expanding range south from OR.
Iris pseudacorus	yellowflag iris	3Limited		C	B	C	2.3	·CaR ·CW ·GV ·NW ·SW	Riparian, wetland areas, esp. southern CA. Limited distribution. Abiotic impacts unknown.
Isatis tinctoria	dyer's woad	2Moderate		B	B	A	3.0	·CaR ·NW ·SN ·MP	Great Basin scrub and grasslands, coniferous forest. More severe impacts in other western states, but can be locally very invasive in northern CA.
Lactuca serriola	prickly lettuce	4Eval No List		D	B	B	3.1	·All CA	Primarily an agricultural and roadside weed
Lepidium latifolium	perennial pepperweed, tall whitetop	1High		A	A	A	3.1	·CA-FP ·GB ·DMoj	Coastal and inland marshes, riparian areas, wetlands, grasslands; potential to invade montane wetlands.
Leucanthemum vulgare	ox-eye daisy	2Moderate		B	B	B	2.5	·CW ·NW ·SN ·SW	Montane meadows, coastal grasslands, coastal scrub. Expanding range, invasiveness varies locally.
Ligustrum lucidum	glossy privet	4Eval No List		D	B	C	3.1	·NW	May prove to be problematic in riparian areas.
Linaria genistifolia ssp. dalmatica	Dalmation toadflax	2Moderate		B	B	B	2.8	·CA-FP	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	·CA-FP	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	·CW ·NW ·SW	Coastal dune, coastal scrub, coastal prairie, riparian.
Lolium multiflorum	Italian ryegrass	2Moderate		A	B	A	2.6	·CA-FP	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	·CA-FP ·GB	Primarily a turf or agricultural weed in CA
Ludwigia hexapetala	Uruguay water-primrose	1High	Alert	A	B	C	2.6	·CW ·NW ·SW	Freshwater aquatic systems. Clarification needed on taxonomic identification.
Ludwigia peploides ssp. montevidensis	creeping water-primrose	1High		A	B	B	2.5	·CW ·GV ·NW ·SN ·SW ·DMoj	Freshwater aquatic systems. Clarification needed on taxonomic identification.
Lupinus arboreus	yellow bush lupine	5Native		B	B	B	3.5	·CW ·NW	Invasive in NW coastal dunes.
Lythrum hyssopifolium	hyssop loosestrife	3Limited		C	B	B	3.0	·CA-FP	Grasslands, wetlands, vernal pools. Widespread. Impacts unknown, but appear to be minor.
Lythrum salicaria	purple loosestrife	1High		A	A	B	3.8	·GV ·NW ·SW ·MP	Wetlands, marshes, riparian areas
Marrubium vulgare	white horehound	3Limited		C	C	B	2.8	·CA-FP ·DMoj	Grasslands scrub, riparian areas. Widespread. Rarely in dense stands. Impacts relatively minor.
Medicago polymorpha	California burclover	3Limited		C	C	A	2.8	·CA-FP	Grasslands. Widespread weed of agriculture and disturbed areas. Impacts in wildlands minor.
Melilotus officinalis	yellow sweetclover	4Eval No List		D	C	C	3.3	·CA-FP ·GB	Present in human-disturbed habitats only
Mentha pulegium	pennyroyal	2Moderate		C	A	A	2.7	·CW ·GV ·NW ·SW	Vernal pools, wetlands. Poisonous to livestock. Spreading rapidly. Impacts largely unknown.
Mesembryanthemum crystallinum	crystalline iceplant	2Moderate	Alert	B	B	C	3.7	·CW ·NW ·SW	Coastal bluffs, dunes, scrubs, grasslands. Limited distribution. Locally problematic, especially in southern CA.
Myosotis latifolia	common forget-me-not	3Limited		C	B	B	2.2	·CA-FP ·DMoj	Coniferous forest, riparian. Little information on impacts.
Myriophyllum aquaticum	parrotfeather	1High	Alert	A	B	C	2.8	·CaR ·CW ·NW ·SW	Freshwater aquatic systems
Nicotiana glauca	tree tobacco	2Moderate		B	B	B	2.5	·GV ·NW ·SN ·SW ·D	Coastal scrub, grasslands, riparian woodland. Abiotic impacts unknown. Impacts vary locally. Rarely in dense stands.
Olea europaea	olive	3Limited		C	B	B	2.5	·CW ·GV ·NW ·SW	A problem in Australia. Currently a rare escape in CA but is of concern due to the possibility of spread from planted groves.
Onopordum acanthium	Scotch thistle	1High		B	B	B	2.9	·CA-FP ·MP	Wet meadows, sage brush, riparian areas
Oxalis corniculata	creeping woodsorrel	4Eval No List		D	C	C	2.2	·All CA	Primarily a turf weed in CA
Oxalis pes-caprae	Bermuda buttercup, buttercup oxalis, yellow oxalis	2Moderate		B	B	B	2.9	·CW ·NW ·SW	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	·CaR ·CW ·NW ·SW	Coastal prairie, grassland, and dunes. Impacts unknown, but can be locally significant.
Pennisetum clandestinum	kikuyugrass	3Limited		C	C	B	2.3	·CW ·NW ·SW	Present at low levels in numerous wildland habitats. Impacts unknown. Common turf weed.
Phalaris aquatica	hardinggrass	2Moderate		B	B	B	2.6	·CW ·NW ·SN ·SW ·DMoj	Coastal sites, especially moist soils. Limited distribution. Can be highly invasive locally.
Phragmites australis	common reed	5Native		B	B	B	2.5	·All CA	Genetic issues make it unclear which strains are native to CA.
Phytolacca americana	common pokeweed	3Limited		C	B	C	2.8	·CA-FP	riparian forest, riparian woodland
Picris echioides	bristly oxtongue	3Limited		C	B	B	2.4	·CA-FP	Coastal prairie, scrub, riparian woodland. Widespread locally. Abiotic impacts unknown.
Pinus radiata cultivars	Monterey pine	5Native		B	B	B	2.6	·NW	Five populations native to CA. Invades coastal scrub and prairie, chaparral.
Piptatherum miliaceum	smilograss	3Limited		C	B	B	2.4	·CW ·GV ·NW ·SN ·SW	Coastal dunes, scrub, riparian, grassland. Expanding range. Impacts largely unknown.
Plantago coronopus	cutleaf plantain	4Eval No List		U	C	B	1.7	·CW ·GV ·NW ·SN ·SW	Impacts unknown. Common on north coast
Plantago lanceolata	buckhorn plantain, English plantain	3Limited		C	C	B	2.1	·CA-FP	Many habitats. Turf weed primarily. Low density and impact in wildlands.
Poa pratensis	Kentucky bluegrass	3Limited		C	B	B	2.7	·All CA	Grasslands scrub, riparian areas. Widespread turf plant. Abiotic impacts unknown.
Polygonum cuspidatum	Japanese knotweed	2Moderate	Alert	B	B	D	2.7	·CaR ·CW ·GV ·NW ·SN	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	·CaR ·CW ·GV ·NW ·SN	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	·All CA	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	·CW ·GV ·NW ·SW ·DMoj	Freshwater aquatic systems. Can be very invasive locally.
Prunus cerasifera	cherry plum	3Limited		C	B	B	1.8	·CW ·NW ·SW	Riparian habitats, chaparral, woodland. Limited distribution. Abiotic impacts unknown.
Pyracantha angustifolia, P. crenulata, P. coccinea	pyracantha, firethorn	3Limited		C	B	B	2.8	·CW ·NW ·SW	Coastal scrub and prairie, riparian areas. Horticultural escape. Impacts unknown or minor.
Ranunculus repens	creeping buttercup	3Limited		C	C	B	2.9	·CaR ·CW ·NW ·SN ·SW	Riparian areas, coniferous forest. Impacts appear to be minor to negligible in most areas.
Raphanus sativus	radish	3Limited		C	C	B	2.5	·CA-FP	Present at low levels in numerous habitats. Widespread in disturbed sites.
Robinia pseudoacacia	black locust	3Limited		C	B	B	2.8	·CA-FP ·GB	Riparian areas, canyons. Severe impacts in southern states. Impacts minor in CA.
Rubus armeniacus	Himalaya blackberry	1High		A	A	A	3.0	·CA-FP	Riparian areas, marshes, oak woodlands
Rumex acetosella	red sorrel, sheep sorrel	2Moderate		B	B	A	2.3	·CA-FP	Many habitats, riparian areas, forest, wetlands. Widespread. Abiotic impacts unknown. Impacts can vary locally.
Rumex crispus	curly dock	3Limited		C	C	A	2.7	·All CA	Grasslands, vernal pool, meadows, riparian. Widespread. Impacts appear to be minor.
Salsola tragus	Russian-thistle	3Limited		C	B	B	2.8	·All CA	Desert dunes and scrub, alkali playa. Widespread. Impacts minor in wildlands.
Sapium sebiferum	Chinese tallowtree	2Moderate	Alert	B	B	C	3.2	·CW ·GV ·NW	Riparian areas. Impacts severe in southeast US. Limited distribution in California, but spreading rapidly regionally.
Saponaria officinalis	bouncingbet	3Limited		C	B	C	2.5	·CW ·GV ·NW ·SW ·GB	Riparian scrub and woodland. Impacts unknown or minor, but appear to be locally variable.
Senecio jacobaea	tansy ragwort	3Limited		C	B	B	2.8	·CA-FP	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	·CA-FP ·DSon	Riparian areas
Silybum marianum	blessed milkthistle	3Limited		C	C	A	3.5	·CA-FP	Grasslands, riparian. Widespread, primarily in disturbed areas Impacts can be higher locally
Sinapis arvensis	wild mustard, charlock	3Limited		C	C	C	2.9	·CA-FP	Grasslands. Primarily in disturbed sites. Impacts minor or unknown in wildlands.
Solanum elaeagnifolium	silverleaf nightshade	4Eval No List		D	B	C	2.8	·CA-FP ·D	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	·All CA	Primarily an agricultural weed
Spartium junceum	Spanish broom	1High		A	B	B	3.2	·CA-FP ·DMoj	Coastal scrub, grasslands, wetlands, oak woodland, forests
Taeniatherum caput-medusae	medusahead	1High		A	A	A	3.4	·CA-FP ·MP	Grasslands, scrub, woodland
Tamarix ramosissima	saltcedar, tamarisk	1High		A	A	A	3.3	·CW ·GV ·NW ·SN ·SW ·SNE ·D	Desert washes, riparian areas, seeps and springs
Tanacetum vulgare	common tansy	2Moderate		B	B	B	2.3	·NW	Riparian areas, forest. Limited distribution. Severe problem in other western states.
Taraxacum officinale	common dandelion	4Eval No List		D	B	B	2.8	·CA-FP ·GB	Primarily a turf weed in CA
Torilis arvensis	hedgeparsley	2Moderate		C	B	B	2.3	·CA-FP	Expanding range. Appear to have only moderate ecological impacts.
Trifolium hirtum	rose clover	2Moderate		C	B	B	2.8	·CA-FP	Grasslands, oak woodland. Widely planted in CA. Impacts relatively minor in most areas.
Ulex europaeus	gorse	1High		A	B	B	2.9	·CaR ·CW ·NW ·SN	Scrub, woodland, forest, coastal grassland
Verbena bonariensis, Verbena litoralis	tall vervain, seashore vervain	4Eval No List		D	B	C	2.1	·CaR ·GV ·NW	Often in disturbed areas of irrigation canals
Vicia villosa	hairy vetch	4Eval No List		D	C	B	2.8	·CA-FP	Primarily an agricultural weed, Widespread but impacts minor in wildlands.
Vinca major	big periwinkle	2Moderate		B	B	B	2.8	·CA-FP ·DMoj	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	·CA-FP	Less common than V. myuros
Vulpia myuros	rattail fescue	2Moderate		B	B	A	3.0	·CA-FP ·D	Coastal sage scrub, chaparral. Widespread. Rarely forms monotypic stands, but locally problematic
Watsonia meriana	bulbil watsonia	3Limited		C	B	C	2.3	·NW	Coastal prairie, coniferous forest. Abiotic impacts unknown, but may be locally dense.
Zantedeschia aethiopica	calla lily	3Limited		C	B	C	2.1	·CW ·NW ·SW	Coastal prairie, wetlands. Impacts high in other countries and local impacts may be high in CA.

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.