Plant Assessment Form

More Centaurea stoebe ssp. micranthos resources

Centaurea stoebe ssp. micranthos

Synonyms: Centaurea maculosa; Centaurea biebersteinii, Centaurea stoebe ssp. stoebe and ssp. maculosa; Centaurea stoebe subsp. australis

Common Names: spotted knapweed

Evaluated on: 1/21/05

List committee review date: 08/07/2005

Re-evaluation date:

Evaluator(s)

Gina Skurka
Cal-IPC
530-400-8992
gmskurka@cal-ipc.org

Joseph DiTomaso
University of California-Davis
Dept. Plant Sci., Mail Stop 4, Davis, CA 95616
530-754-8715
jmditomaso@ucdavis.edu

List committee members

Carla Bossard
John Randall
Carri Pirosko
Dan Gluesenkamp
Gina Skurka
Brianna Richardson

General Comments

Removed second scientific name, Centaurea maculosa, and added it to the synonym line 3/28/17. Ramona Robison

Table 2. Criteria, Section, and Overall Scores

Overall Score? High

Alert Status? No Alert

Documentation? 3.5 out of 5

Score

Documentation

1.1

?Impact on abiotic ecosystem processes

B. Moderate

Reviewed Scientific Publication

Impact?
Four-part score BAAD Total Score
A

1.2

?Impact on plant community

A. Severe

Reviewed Scientific Publication

1.3

?Impact on higher trophic levels

A. Severe

Reviewed Scientific Publication

1.4

?Impact on genetic integrity

D. None

Other Published Material

2.1

?Role of anthropogenic and natural disturbance in establishment

B. Moderate

Reviewed Scientific Publication

Invasiveness?
Total Points
16 Total Score B

2.2

?Local rate of spread with no management

A. Increases rapidly

Other Published Material

2.3

?Recent trend in total area infested within state

B. Increasing less rapidly

Observational

2.4

?Innate reproductive potential
(see Worksheet A)

A. High

Reviewed Scientific Publication

2.5

?Potential for human-caused dispersal

B. Moderate

Reviewed Scientific Publication

2.6

? Potential for natural long-distance dispersal

B. Occasional

Reviewed Scientific Publication

2.7

?Other regions invaded

B. Invades 1 or 2 ecological types

Other Published Material

3.1

?Ecological amplitude/Range
(see Worksheet C)

A. Widespread

Other Published Material

Distribution?
Total Score B

3.2

?Distribution/Peak frequency
(see Worksheet C)

D. Very low

Observational

Table 3. Documentation

Scores are explained in the "Criteria for Categorizing Invasive Non-Native Plants that Threaten Wildlands".

Section 1: Impact
Question 1.1 Impact on abiotic ecosystem processes? Consider the impact on the natural range and variation of abiotic ecosystem processes and system-wide parameters in ways that significantly diminish the ability of native species to survive and reproduce. Alterations that determine the types of communities that can exist in a given area are of greatest concern. Examples of abiotic processes include: - fire occurrence, frequency, and intensity; - geomorphological changes such as erosion and sedimentation rates; - hydrological regimes, including soil water table; - nutrient and mineral dynamics, including salinity, alkalinity, and pH; - light availability (e.g. when an aquatic invader covers an entire water body that would otherwise be open). Select the one letter below that best describes this species' most severe impact on an abiotic ecosystem process: A. Severe, possibly irreversible, alteration or disruption of an ecosystem process. B. Moderate alteration of an ecosystem process. C. Minor alteration of an ecosystem process. D. Negligible perceived impact on an ecosystem process. U. Unknown.	B Reviewed Scientific Publication
Identify ecosystem processes impacted: Stout elongated taproot may decrease soil moisture. Knapweed infestation can increase surface run-off and sedimentation. They are poor protectors of soil and water resources and they pose a wildfire threat. Success could be attributed to greater use, or more efficient use, of available soil nitrogen. Soil N often limits growth on semi-arid grasslands. Greater or more efficient use of soil N by spotted knapweed may inhibit establishment, survival, or reproduction of native grassess, if this occurred, but it doesn't. Also, Centaurea's success as an invasive species in North america cannot be attributed to greater use of soil water or greater water-use efficiency than native grasses. Knapweed infestation on bunchgrass rangeland is detrimental to water and soil resources. Lacy 1989 determined that surface water runoff and stream sediment yield were 56 and 192% higher, respectively, for spotted knapweed-dominated sites compared to bunchgrass-dominated sites. Bareground and water infiltration rates were greater on sites with unclipped bunchgrass than on those with spotted knapweed. Moderate alteration of ecosystem processes by decreasing soil moisture and facilitating erosion. Sources of information: Hoffman, Kerns. Wisconsin Manual of Control Recommendations for Ecologically Invasive Plants. Pgs 44-47. 1997. Roche, B.F. Jr. , C.T. Roche. Identification, Introduction, Distribution, Ecology, and Economics of Centaurea Species. Noxious Range Weeds. 1991. 274-291. Ed. James L.F. et al. Westview Press, Boulder, San Francisco, Oxford. Blicker, P.S., B.E. Olson, and R.Engel. 2002. Traits of the invasive Centaurea maculosa and two native grasses: effect of N supply. Plant and Soil V. 247(2) P. 261-269. Blicker, P.S., B.E. Olson, and J.M. Wraith. Water use and water-use efficiency of the invasive Centaurea maculosa and three native grasses. Plant and Soil. v. 254(2) p. 371-381. Sheley, R.L., Jacobs, J.S., Carpinelli M.F., Distribution, Biology and of Diffuse Knapweed (Centaurea diffusa) and Spotted Knapweed (Centaurea maculosa). Weed Technology 12: 353-362. 1998.
Question 1.2 Impact on plant community composition, structure, and interactions? Consider the cumulative ecological impact of this species to the plant communities it invades. Give more weight to changes in plant composition, structure, and interactions that involve rare or keystone species or rare community types. Examples of severe impacts include: - formation of stands dominated (>75% cover) by the species; - occlusion (>75% cover) of a native canopy, including a water surface, that eliminates or degrades layers below; - significant reduction or extirpation of populations of one or more native species. Examples of impacts usually less than severe include: - reduction in propagule dispersal, seedling recruitment, or survivorship of native species; - creation of a new structural layer, including substantial thatch or litter, without elimination or replacement of a pre-existing layer; - change in density or depth of a structural layer; - change in horizontal distribution patterns or fragmentation of a native community; - creation of a vector or intermediate host of pests or pathogens that infect native plant species. Select the one letter below that best describes this species' impact on community composition, structure and interactions: A. Severe alteration of plant community composition, structure, or interactions. B. Moderate alteration of plant community composition. C. Minor alteration of community composition. D. Negligible impact known; causes no perceivable change in community composition, structure, or interactions. U. Unknown.	A Reviewed Scientific Publication
Identify type of impact or alteration: Spotted knapweed often attains high densities on sunny wild lands, even those undisturbed by human or livestock activitiy. Knapweed thends to dominate sites at the expense of community diversity or forage production. C. maculosa reduces the productivity of desirable forage plants and floristic diversity. It has the ability to invade mature native bunchgrass communities. Decreased bluebunch wheatgrass yield was correlated with increased production of spotted knapweed. Bluebunch wheatgrass-rough fescue production was reduced by 88% by knapweed invasion. Moderate alteration of plant community composition by reduction in survivorship of native grasses Sources of information: Hoffman, Kerns. Wisconsin Manual of Control Recommendations for Ecologically Invasive PLants. Pgs. 44-47. 1997. Blicker, P.S., B.E. Olson, and R.Engel. 2002. Traits of the invasive Centaurea maculosa and two native grasses: effect of N supply. Plant and Soil V. 247(2) P. 261-269. Lacey, J.R., P. Husby, and G. Handl, Observations on Spotted and Diffuse Knapweed Invasion into Ungrazed Bunchgrass Communities in Western Montana. Rangelands 12 (1). 1990. 30-32. Sheley, R.L., Jacobs, J.S., Carpinelli M.F., Distribution, Biology and of Diffuse Knapweed (Centaurea diffusa) and Spotted Knapweed (Centaurea maculosa). Weed Technology 12: 353-362. 1998.
Question 1.3 Impact on higher trophic levels? Consider the cumulative impact of this species on the animals, fungi, microbes, and other organisms in the communities that it invades. Although a non-native species may provide resources for one or a few native species (e.g. by providing food, nesting sites, etc.), the ranking should be based on the species' net impact on all native species. Give more weight to changes in composition and interactions involving rare or keystone species or rare community types. Examples of severe impacts include: - extirpation or endangerment of an existing native species or population; - elimination or significant reduction in native species' nesting or foraging sites, cover, or other critical resources (i.e., native species habitat), including migratory corridors. Examples of impacts that are usually less than severe include: - minor reduction in nesting or foraging sites, cover, etc. for native animals; - minor reduction in habitat connectivity or migratory corridors; - interference with native pollinators; - injurious components, such as awns or spines that damage the mouth and gut of native wildlife species, or production of anti-digestive or acutely toxic chemical that can poison native wildlife species. Select the one letter below that best describes this species' impact on community composition and interactions: A. Severe alteration of higher trophic populations, communities, or interactions. B. Moderate alteration of higher trophic level populations, communities, or interactions. C. Minor alteration of higher trophic level populations, communities or interactions. D. Negligible impact; causes no perceivable change in higher trophic level populations, communities, or interactions. E. Unknown.	A Reviewed Scientific Publication
Identify type of impact or alteration: Knapweeds are grazed by dear and sheep. These plants also provide nectar and pollen for domestic bees. Domestic animals and wildlife such as elk rely on range grasses and herbs for up to 80% of diet. Knapweed encroachment can destroy the forage base and would result in a significant decline in deer and elk numbers. Detrimental to range resource values because they have low platability to livestock and wildlife. Spotted knapweed reduces livestock forage and negatively impacts wildlife. Elk use was reduced by 98% on spotted knapweed-dominated range compared to bunchgrass-dominated sites. Spoon 1983 predicted a loss of 220 elk annually in Montana because of spotted knapweed infestations on winter range. Sources of information: Knapweed: Its Cost to British Columbia. Pamphlet from Province of British Columbia, Ministry of Agriculture, Fisheries and Food. Roche, B.F. Jr. , C.T. Roche. Identification, Introduction, Distribution, Ecology, and Economics of Centaurea Species. Noxious Range Weeds. 1991. 274-291. Ed. James L.F. et al. Westview Press, Boulder, San Francisco, Oxford. Sheley, R.L., Jacobs, J.S., Carpinelli M.F., Distribution, Biology and of Diffuse Knapweed (Centaurea diffusa) and Spotted Knapweed (Centaurea maculosa). Weed Technology 12: 353-362. 1998.
Question 1.4 Impact on genetic integrity? Consider whether the species can hybridize with and influence the proportion of individuals with non-native genes within populations of native species. Mechanisms and possible outcomes include: - production of fertile or sterile hybrids that can outcompete the native species; - production of sterile hybrids that lower the reproductive output of the native species. Select the one letter below that best describes this species' impact on genetic integrity: A. Severe (high proportion of individuals). B. Moderate (medium proportion of individuals). C. Minor (low proportion of individuals). D. No known hybridization. U. Unknown.	D Other Published Material
none No native Centaurea species in California. Sources of information: Hickman, J. (ed.) 1993. The Jepson Manual, Higher Plants of California. University of California Press. Berkeley, CA.
Section 2: Invasiveness
Question 2.1 Role of anthropogenic and natural disturbance in establishment? Assess this species' dependence on disturbance: both human and natural: for establishment in wildlands. Examples of anthropogenic disturbances include: - grazing, browsing, and rooting by domestic livestock and feral animals; - altered fire regimes, including fire suppression; - cultivation; - silvicultural practices; - altered hydrology due to dams, diversions, irrigation, etc.; - roads and trails; - construction; - nutrient loading from fertilizers, runoff, etc. Examples of natural disturbance include: - wildfire; - floods; - landslides; - windthrow; - native animal activities such as burrowing, grazing, or browsing. Select the first letter in the sequence below that describes the ability of this species to invade wildlands: A. Severe invasive potential: this species can establish independent of any known natural or anthropogenic disturbance. B. Moderate invasive potential: this species may occasionally establish in undisturbed areas but can readily establish in areas with natural disturbances. C. Low invasive potential: this species requires anthropogenic disturbance to establish. D. No perceptible invasive potential: this species does not establish in wildlands (though it may persist from former cultivation). U. Unknown.	A Other Published Material
Describe role of disturbance: Spotted knapweed has invaded relatively undisturbed native plant communities and natural areas as well as heavily disturbed sites. Moderate invasive potential - this species may occasionally establish in undistrubed areas but can readily establish in areas with natural disturbances. Sources of information: Hoffman, Kerns. Wisconsin Manual of Control Recommendations for Ecologically Invasive Plants. Pgs 44-47. 1997. Roche, B.F. Jr. , C.T. Roche. Identification, Introduction, Distribution, Ecology, and Economics of Centaurea Species. Noxious Range Weeds. 1991. 274-291. Ed. James L.F. et al. Westview Press, Boulder, San Francisco, Oxford. Blicker, P.S., B.E. Olson, and R.Engel. 2002. Traits of the invasive Centaurea maculosa and two native grasses: effect of N supply. Plant and Soil V. 247(2) P. 261-269.
Question 2.2 Local rate of spread with no management? Assess this species' rate of spread in existing localized infestations where the proportion of available habitat invaded is still small when no management measures are implemented. Select the one letter below that best describes the rate of spread: A. Increases rapidly (doubling in <10 years) B. Increases, but less rapidly C. Stable D. Declining U. Unknown	A Other Published Material
Describe rate of spread: Has spread rapidly in most other western states. Sources of information: Duncan, C.L. and J.K. Clark (eds.). 2005. Invasive plants of range and wildlands and their environmental, ecological, and societal impacts. WSSA.
Question 2.3 Recent trend in total area infested within state? Assess the overall trend in the total area infested by this species statewide. Include current management efforts in this assessment and note them. Select the one letter below that best describes the current trend: A. Increasing rapidly (doubling in total range statewide in <10 years) B. Increasing, but less rapidly C. Stable D. Declining U. Unknown	B Observational
Describe trend: Through the efforts of CDFA, spotted knapweed populations have remained about stable over the past few years. Without these efforts it is very likely that the infestations would expand exponentially, as they have in so many other states. Sources of information: DiTomaso, observational.
Question 2.4 Innate reproductive potential? Assess the innate reproductive potential of this species. Worksheet A is provided for computing the score.	A Reviewed Scientific Publication
Describe key reproductive characteristics: Reproduces solely by seed. Individual flower heads bloom from late June through August for 2-6 days each. The bracts reopen after about 20 days and scatter seeds. Plants average about 1,000 seeds per plant. Seeds are viable for seven years, and germinate throughout the growing season. Seed production was 1,000-fold that needed to maintain observed levels of infestation. Lives up to 9 years and is able to produce seeds each year. Seed production of spotted knapweed ranges from 5,000 to 40,000 seeds/m2, with more seeds produced during wet years. High. 7 points Sources of information: Hoffman, Kerns. Wisconsin Manual of Control Recommendations for Ecologically Invasive Plants. Pgs 44-47. 1997. Schirman R. Seed Production and Spring Seedling Establishment of Diffuse and spotted Knapweed. Journal of Range Management 34(1). 1981. 45-47. Sheley, R.L., Jacobs, J.S., Carpinelli M.F., Distribution, Biology and of Diffuse Knapweed (Centaurea diffusa) and Spotted Knapweed (Centaurea maculosa). Weed Technology 12: 353-362. 1998.
Question 2.5 Potential for human-caused dispersal? Assess whether this species is currently spread: or has high potential to be spread: by direct or indirect human activity. Such activity may enable the species to overcome natural barriers to dispersal that would not be crossed otherwise, or it may simply increase the natural dispersal of the species. Possible mechanisms for dispersal include: - commercial sales for use in agriculture, ornamental horticulture, or aquariums; - use as forage, erosion control, or revegetation; - presence as a contaminant (seeds or propagules) in bulk seed, hay, feed, soil, packing materials, etc.; - spread along transportation corridors such as highways, railroads, trails, or canals; - transport on boats or boat trailers. Select the one letter below that best describes human-caused dispersal and spread: A. High: there are numerous opportunities for dispersal to new areas. B. Moderate: human dispersal occurs, but not at a high level. C. Low: human dispersal is infrequent or inefficient. D. Does not occur. U. Unknown.	B Reviewed Scientific Publication
Identify dispersal mechanisms: People spread knapweed as it is easily caught up and transported great distances in the undercarriage and doors of recreational vehicles, trains, light aircraft landing at infested air strips, logging trucks and heavy machinery. It is also spread by florists who use knapweed in dried floral arrangements, movement of hay from knapweed infested to non-infested areas. Spotted knapweed flower heads also become attached to the undercarriages of vehicles, are transported long distances in mud, and commonly become attached to or drop into shoes. May also be transported in wood brought from Washington for log cabin kits. There are numerous opportunities for dispersal to new areas, but not as high as some other species. Sources of information: Knapweed: Its Cost to British Columbia. Pamphlet from Province of British Columbia, Ministry of Agriculture, Fisheries and Food. Sheley, R.L., Jacobs, J.S., Carpinelli M.F., Distribution, Biology and of Diffuse Knapweed (Centaurea diffusa) and Spotted Knapweed (Centaurea maculosa). Weed Technology 12: 353-362. 1998.
Question 2.6 Potential for natural long-distance dispersal? We have chosen 1 km as the threshold of "long-distance." Assess whether this species is frequently spread, or has high potential to be spread, by animals or abiotic mechanisms that can move seed, roots, stems, or other propagules this far. The following are examples of such natural long-distance dispersal mechanisms: - the species' fruit or seed is commonly consumed by birds or other animals that travel long distances; - the species' fruits or seeds are sticky or burred and cling to feathers or hair of animals; - the species has buoyant fruits, seeds, or other propagules that are dispersed by flowing water; - the species has light propagules that promote long-distance wind dispersal; - The species, or parts of it, can detach and disperse seeds as they are blown long distances (e.g., tumbleweed). Select the one letter below that best describes natural long-distance dispersal and spread: A. Frequent long-distance dispersal by animals or abiotic mechanisms. B. Occasional long-distance dispersal by animals or abiotic mechanisms. C. Rare dispersal more than 1 km by animals or abiotic mechanisms. D. No dispersal of more than 1 km by animals or abiotic mechanisms. U. Unknown.	B Reviewed Scientific Publication
Identify dispersal mechanisms: Spread by cattle, deer, and elk may pick up the weed and disperse it, and some bird species and small rodents eat knapweed seed. Soil disturbance provides an ideal seedbed for new knapweed infestation. Spotted knapweed plants do not break off at ground level, and populations are largely extended through peripheral enlargement of existing stands. Movement of stem by wind or passing animals can flick the loosely held achenes up to 1 m from the parent plant. Long distance transport occurs when achenes become attached to passing animals, or by rodents and birds. Long-distnace dispersal by animals or abiotic mechanisms can occur but is not the primarily means of dispersal. Sources of information: Knapweed: Its Cost to British Columbia. Pamphlet from Province of British Columbia, Ministry of Agriculture, Fisheries and Food. Sheley, R.L., Jacobs, J.S., Carpinelli M.F., Distribution, Biology and of Diffuse Knapweed (Centaurea diffusa) and Spotted Knapweed (Centaurea maculosa). Weed Technology 12: 353-362. 1998.
Question 2.7 Other regions invaded? Assess whether this species has invaded ecological types in other states or countries outside its native range that are analogous to ecological types not yet invaded in your state (see Worksheets B, C, and D for California, Arizona, and Nevada, respectively, in Part IV for lists of ecological types). This information is useful in predicting the likelihood of further spread within your state. Select the one letter below that best describes the species' invasiveness in other states or countries, outside its native range. A. This species has invaded 3 or more ecological types elsewhere that exist in your state and are as yet not invaded by this species (e.g. it has invaded Mediterranean grasslands, savanna, and maquis in southern Europe, which are analogous to California grasslands, savanna, and chaparral, respectively). B. Invades 1 or 2 ecological types that exist but are not yet invaded in your state. C. Invades elsewhere but only in ecological types that it has already invaded in the state. D. Not known as an escape anywhere else. U. Unknown.	B Other Published Material
Identify other regions: This plant was probably introduced in the late 1890s as a contaminant in alfalfa or hay seed from Europe and Asia. Spotted knapweed, a native of Europe, was collected on Vancouver Island, British Columbia, in 1905 and San Juan Island, Washington, in 1923. By the 1930s it was common in Montana and northern Idaho. Sources of information: Duncan, C.L. and J.K. Clark (eds.). 2005. Invasive plants of range and wildlands and their environmental, ecological, and societal impacts. WSSA. Hoffman, Kerns. Wisconsin Manual of Control Recommendations for Ecologically Invasive Plants. Pgs 44-47. 1997.
Section 3: Distribution
Question 3.1 Ecological amplitude/Range? Refer to Worksheet C and select the one letter below that indicates the number of different ecological types that this species invades. A. Widespread: the species invades at least three major types or at least six minor types. B. Moderate: the species invades two major types or five minor types. C. Limited: the species invades only one major type and two to four minor types. D. Narrow: the species invades only one minor type. U. Unknown.	A Other Published Material
Can occur in Great Basin grasslands, foothill prairie, riparian habitats, along gravel bars. Habitats based on review committee observations. Sources of information: Duncan, C.L. and J.K. Clark (eds.). 2005. Invasive plants of range and wildlands and their environmental, ecological, and societal impacts. Weed Science Society of America. Carla Bossard, St. Mary's College; John Randall, The Nature Conservancy; Carri Pirosko, California Dept. of Food and Agriculture, pers. obs.
Question 3.2 Distribution/Peak frequency? To assess distribution, record the letter that corresponds to the highest percent infested score entered in Worksheet C for any ecological type.	D Observational
Describe distribution: Not commonly encountered because of the efforts of CDFA Sources of information: DiTomaso, observational.

Worksheet A - Innate reproductive potential

Reaches reproductive maturity in 2 years or less	Yes
Dense infestations produce >1,000 viable seed per square meter	Yes
Populations of this species produce seeds every year.	Yes
Seed production sustained over 3 or more months within a population annually	No
Seeds remain viable in soil for three or more years	Yes
Viable seed produced with both self-pollination and cross-pollination	Unknown
Has quickly spreading vegetative structures (rhizomes, roots, etc.) that may root at nodes	No
Fragments easily and fragments can become established elsewhere	No
Resprouts readily when cut, grazed, or burned	Yes
Total points:	7
Total unknowns:	1
Total score:	A? Scoring Criteria for Worksheet A A. High reproductive potential (6 or more points). B. Moderate reproductive potential (4-5 points). C. Low reproductive potential (3 points or less and less than 3 Unknowns). U. Unknown (3 or fewer points and 3 or more Unknowns).

Related traits:

Worksheet B - Arizona Ecological Types is not included here

Worksheet C - California Ecological Types

(sensu Holland 1986)

Major Ecological Types	Minor Ecological Types	Code? A means >50% of type occurrences are invaded; B means 20% to 50%; C means 5% to 20%; D means present but <5%; U means unknown (unable to estimate percentage of occurrences invaded)
Marine Systems	marine systems
Freshwater and Estuarine	lakes, ponds, reservoirs
Aquatic Systems	rivers, streams, canals
Aquatic Systems	estuaries
Dunes	coastal
	desert
	interior
Scrub and Chaparral	coastal bluff scrub
	coastal scrub
	Sonoran desert scrub
	Mojavean desert scrub (incl. Joshua tree woodland)
	Great Basin scrub	D, < 5%
	chenopod scrub
	montane dwarf scrub
	Upper Sonoran subshrub scrub
	chaparral
Grasslands, Vernal Pools, Meadows, and other Herb Communities	coastal prairie
	valley and foothill grassland	D, < 5%
	Great Basin grassland	D, < 5%
	vernal pool
	meadow and seep	D, < 5%
	alkali playa
	pebble plain
Bog and Marsh	bog and fen
Bog and Marsh	marsh and swamp
Riparian and Bottomland habitat	riparian forest	D, < 5%
	riparian woodland
	riparian scrub (incl.desert washes)
Woodland	cismontane woodland	D, < 5%
	piñon and juniper woodland
	Sonoran thorn woodland
Forest	broadleaved upland forest
	North Coast coniferous forest
	closed cone coniferous forest
	lower montane coniferous forest	D, < 5%
	upper montane coniferous forest
	subalpine coniferous forest
Alpine Habitats	alpine boulder and rock field
Alpine Habitats	alpine dwarf scrub
	Amplitude (breadth):	A
	Distribution (highest score):	D

Infested Jepson Regions

Click here for a map of Jepson regions

CA Floristic Province
Cascade Range
Central West
Great Valley
Northwest
Sierra Nevada
Southwest
Great Basin Province
Modoc Plateau
Sierra Nevada East
Desert Province
Mojave Desert

California Invasive Plant Council

Protecting California’s environment and economy from invasive plants

Plant Assessment Form

More Centaurea stoebe ssp. micranthos resources

Centaurea stoebe ssp. micranthos

Evaluator(s)

List committee members

General Comments

Table 2. Criteria, Section, and Overall Scores

Table 3. Documentation

Worksheet A - Innate reproductive potential

Related traits:

Worksheet C - California Ecological Types

Infested Jepson Regions