Source: California Invasive Plant Council


URL of this page: http://www.cal-ipc.org/site/paf/259
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Cal-IPC Plant Assessment Form

For use with "Criteria for Categorizing Invasive Non-Native Plants that Threaten Wildlands"
by the California Invasive Plant Council and the Southwest Vegetation Management Association

Table 1. Species and Evaluator Information

Species name
(Latin binomial):
The official Latin binomial name for this species. Specify only one name here. Additional species names may go into the Synonyms field.

Arctotheca prostrata

Synonyms:
Additional Latin binomial names for this species. Separate multiple names with a ; character. Please avoid narrative descriptions, and list only the binomial names.
Arctotheca calendula (infertile forms)
Common names:
Common names for this species. Separate multiple names with a ; character.
capeweed; South African capeweed; cape dandelion; cape gold
Evaluation date:
The date(s) when this species PAF was filled out, modified, or reviewed. This is free-form text, so it may include multiple dates or other notes.
12/21/04
Evaluator #1 Elizabeth Brusati, project manager
California Invasive Plant Council
1442A Walnut St. #462, Berkeley, CA 94709
510-843-3902
edbrusati@cal-ipc.org
Evaluator #2 Peter J. Warner; ecologist
California State Parks
P. O. Box 603, Little River, CA 95456
707-937-9172; 707-937-2278
corylus@earthlink.net
List committee members: Carla Bossard, John Randall, Cynthia Roye, Jake Sigg, Peter Warner
Committee review date: 2/11/05
List date:
Re-evaluation date(s):
General comments
on this assessment:
Enter any additional notes about this assessment, such as factors affecting the reliability or completeness of the answers, likely affects of impacts, or research which is not specific to California but is still relevant in the evaluation of this species.
Removed second scientific name, Arctotheca calendula (infertile forms), and added it to the synonym line 3/28/17. Ramona Robison

Table 2. Criteria, Section, and Overall Scores

Overall Score

Plant scoring matrix
Based on letter scores from Sections 1 through 3 below

ImpactInvasivenessDistribution
AA BAnyHighNo Alert
AC DAnyModerateAlert
BA BA BModerateNo Alert
BA BC DModerateAlert
BC DAnyLimitedNo Alert
CAA BModerateNo Alert
CAC DLimitedNo Alert
CBAModerateNo Alert
CBB DLimitedNo Alert
CCAnyLimitedNo Alert
DAnyAnyNot ListedNo Alert

Moderate

Alert Status

Plant scoring matrix
Based on letter scores from Sections 1 through 3 below

ImpactInvasivenessDistributionAlert
AA or BC or DAlert
BA or BC or DAlert

No Alert

Documentation

The total documentation score is the average
of Documentation scores given in Table 2.

Reviewed Scientific Publication4 points
Other Published Material3 points
Observational2 points
Anecdotal1 points
Unknown or No Information0 points

2.5 out of 5

Score Documentation
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. Moderate Other Published Material
Impact
Section 1 Scoring Matrix
Q 1.1Q 1.2Q 1.3Q 1.4Score
AAAnyAnyA
ABA,BAnyA
ABC,D,UAnyB
AC,D,UAnyAnyB
BAAAnyA
BABAA
BAB,CB-D,UB
BAC,D,UAA
BAC,D,UB-D,UB
BBAAA
BC,D,UAAB
BB-DAB-D,UB
BB-DB-D,UAnyB
BD,UC,D,UA-BB
BD,UC,D,UC,D,UC
C-D,UAAAnyA
CBAAnyB
CA,BB-D,UAnyB
CC,D,UAnyAnyC
DA,BBAnyB
DA,BC,D,UAnyC
DCAnyAnyC
DD,UAnyAnyD
UAB,CAnyB
UB,CA,BAnyB
UB,CC,D,UAnyC
UUAnyAnyU


Four-part score
BBBD

Total Score
B
1.2 Impact on plant community
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.
B. Moderate Other Published Material
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.
B. Moderate
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. None Reviewed Scientific Publication
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.
C. Low Observational
Invasiveness
Section 2 Scoring Matrix
Total pointsScore
17-21A
11-16B
5-10C
0-4D
More than two U’sU


Total Points
13

Total Score
B
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. Increases rapidly Other Published Material
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. Increasing less rapidly Observational
2.4 Innate reproductive potential
(see Worksheet A)
Assess the innate reproductive potential of this species. Worksheet A is provided for computing the score.
B. Moderate Reviewed Scientific Publication
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.
A. High Reviewed Scientific Publication
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.
D. None
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. Invades 1 or 2 ecological types Other Published Material
3.1 Ecological amplitude/Range
(see Worksheet C)
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. Widespread Other Published Material
Distribution
Section 3 Scoring Matrix
Q 3.1Q 3.2Score
AA, BA
AC,D,UB
BAA
BB,CB
BDC
CA,BB
CC,DC
DAB
DB,CC
DDD
A,BUC
C,DUD
UUU


Total Score
B
3.2 Distribution/Peak frequency
(see Worksheet C)
To assess distribution, record the letter that corresponds to the highest percent infested score entered in Worksheet C for any ecological type.
C. Low Observational

Table 3. Documentation

Scores are explained in the "Criteria for Categorizing Invasive Non-Native Plants that Threaten Wildlands".
Short citations may be used in this table. List full citations at end of this table.

Section 1: Impact

Other Published Material B 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.
Identify ecosystem processes impacted:
Light availability, water availability, space Creates a dense monoculture that blocks light. Aggressive competitor for water and space. Scoring as B because I'm not sure if space is considered an "ecosystem process,"or if this change is irreversible.

Sources of information:
Alvarez, M. 2000. Arctotheca calendula pp. 49-52 in Bossard, C. M., J. M. Randall, and M. C. Hoshovsky (ed.) Invasive plants of California's wildlands. University of California Press. Berkeley, CA.

Other Published Material B 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.
Identify type of impact or alteration:
Rapidly overgrows other species to form dense monocultures. Aggressive competitor for water and space.

Sources of information:
Alvarez, M. 2000. Arctotheca calendula pp. 49-52 in Bossard, C. M., J. M. Randall, and M. C. Hoshovsky (ed.) Invasive plants of California's wildlands. University of California Press. Berkeley, CA.

B 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.
Identify type of impact or alteration:
Eaten by livestock, but sometimes poisonous. Used for pollen by beekeepers in Australia (1). However, another reference claims it is not poisonous (2). Not known to be eaten by California wildlife or invetebrates (3). Scoring as B based on severe changes to plant community that could impact foraging by wildlife dependent on grasses, although there is no specific information on how capeweed invasion affects higher trophic levels.

Sources of information:
1. Anonymous. Cape weed. http://weeds.tassie.net.au/txts/capeweed.html 2. McIvor, J.G., and D. F. Smith. 1972. Competitive growth of capeweed (Arctotheca calendula) and some annual pasture species. Australian Journal of Experimental Agriculture and Animal Husbandry. 13:185-189 3. Alvarez 2000

Reviewed Scientific Publication D 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.
Identify impacts:
none no closely related native species

Sources of information:
Alvarez 2000

Section 2: Invasiveness

Observational C 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.
Describe role of disturbance:
1. Common along roadsides and disturbed land in native habitat; appears to require either deliberate or incidental disturbance for establishment (2) I've never seen this plant in the wild in undisturbed areas, and in almost every case, the plant appears to have been dumped or planted where it is growing; I expect that it is highly dependent on human assistance for establishment in the wild (2).

Sources of information:
1. Wood, H. 1994. The introduction and spread of capeweed, Arctotheca calendula ( L.) Levyns (Asteraceae). Plant Protection Quarterly. 9:94-100 2. Warner, PJ. Personal observations. Marin, Sonoma, Mendocino Counties, 1996-2005. 707/937-2278; corylus@earthlink.net

Other Published Material A 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
Describe rate of spread:
A small plant can cover as much as 200 square feet in 1-2 years. If planted 1 foot apart for landscaping, plants will spread to full cover in 6 months.

Sources of information:
Alvarez 2000, citing gardening books

Observational B 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
Describe trend:
At least slowly increasing, since it is still planted in landscapes, and people still dump the plant along roads, where mowing facilitates its spread (1). Some individuals have also been known to plant this weed intentionally in wildland areas (2). Personal observations based on the widespread use of this plant in landscaping and debris-dumping (1). 2. Alvarez, M. 1996. Anecdotes from Golden Gate National Recreation Area, as told to P. Warner.

Sources of information:
Warner, PJ. Personal observations. Marin, Sonoma, Mendocino Counties, 1996-2005. 707/937-2278; corylus@earthlink.net

Reviewed Scientific Publication B Question 2.4 Innate reproductive potential
Assess the innate reproductive potential of this species. Worksheet A is provided for computing the score.
Describe key reproductive characteristics:
Sterile variety. All reproduction is by rapidly-growing stolons that can root at nodes. Stolons form from late winter through spring until water availability decreases. A small plant can cover up to 200 square ft/yr

Sources of information:
Alvarez 2000

Reviewed Scientific Publication A 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.
Identify dispersal mechanisms:
Introduced for horticulture. Still widely used in landscaping (1,3). Can be spread by mechanical equipment along roads (1,3). Most populations in southern Australia are near water, stockyards, or railways (2). Found in Cal-IPC nursery survey 2004

Sources of information:
1. Alvarez 2000 2. Wood 1994. 3. Warner, PJ. Personal observations. Marin, Sonoma, Mendocino Counties, 1996-2005. 707/937-2278; corylus@earthlink.net

D 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.
Identify dispersal mechanisms:
All reproduction is vegetative, so no seeds available for dispersal. Seems to require human activity to be spread.

Sources of information:
Inferred from information in Alvarez 2000

Other Published Material B 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.
Identify other regions:
1. southern Australia: "widespread and successful colonizer, responsible for significant economic losses to cropping and pasture industries, occupies regions with climate similar to its native South Africa" Scoring as B based on the fact that it is widespread in Australia, which has similar habitats to parts of California, but capeweed has not yet invaded areas such as the central valley where it has the potential to grow (2)

Sources of information:
1, Wood 1994 2. Alvarez 2000

Section 3: Distribution

Other Published Material A 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.
Describe ecological amplitude, identifying date of source information and approximate date of introduction to the state, if known:
As of 2000, was in Marin and Humboldt counties (1). Widespread along Sonoma and Mendocino coast, especially in disturbed coastal terrace prairie and seasonally wet areas (2). Could probably survive in most of California west of Sierra Nevada mountains.

Sources of information:
1. Alvarez 2000 2. Warner, PJ. Personal observations. Marin, Sonoma, Mendocino Counties, 1996-2005. 707/937-2278; corylus@earthlink.net

Observational C 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.
Describe distribution:
Most common in coastal prairie, especially adjacent to roads, trails, or historical homesteads or farms. Often seen adjacent to habitual roadside dumping sites. Also seen occasionally in coastal wetlands and coastal scrub, also adjacent to human-disturbed sites or domestic landscapes (1). Purely observational, but lots of observations.

Sources of information:
1. Warner, PJ. Personal observations. Marin, Sonoma, Mendocino Counties, 1996-2005. 707/937-2278; corylus@earthlink.net

Worksheet A - Innate reproductive potential

Reaches reproductive maturity in 2 years or less Yes, 1 points
Dense infestations produce >1,000 viable seed per square meter No
Populations of this species produce seeds every year. No
Seed production sustained over 3 or more months within a population annually No
Seeds remain viable in soil for three or more years No
Viable seed produced with both self-pollination and cross-pollination No
Has quickly spreading vegetative structures (rhizomes, roots, etc.) that may root at nodes Yes, 1 points
Fragments easily and fragments can become established elsewhere Yes, 2 points
Resprouts readily when cut, grazed, or burned Yes, 1 points
Total points: 5
Total unknowns: 0
Total score: B
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).
Note any related traits:
Return to Table 2

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 Systemsmarine systems
Freshwater and Estuarine lakes, ponds, reservoirs
Aquatic Systemsrivers, streams, canals
estuaries
Dunescoastal
desert
interior
Scrub and Chaparralcoastal bluff scrub
coastal scrubD. < 5%
Sonoran desert scrub
Mojavean desert scrub (incl. Joshua tree woodland)
Great Basin scrub
chenopod scrub
montane dwarf scrub
Upper Sonoran subshrub scrub
chaparral
Grasslands, Vernal Pools, coastal prairieC. 5% - 20%
Meadows, and other Herbvalley and foothill grassland
CommunitiesGreat Basin grassland
vernal pool
meadow and seep
alkali playa
pebble plain
Bog and Marshbog and fen
marsh and swampD. < 5%
Riparian and Bottomland habitatriparian forest
riparian woodland
riparian scrub (incl.desert washes)
Woodlandcismontane woodland
piñon and juniper woodland
Sonoran thorn woodland
Forestbroadleaved upland forest
North Coast coniferous forest
closed cone coniferous forest
lower montane coniferous forest
upper montane coniferous forest
subalpine coniferous forest
Alpine Habitatsalpine boulder and rock field
alpine dwarf scrub
Amplitude (breadth)  
Distribution (highest score)  
Return to Table 2

Addendum J - Jepson Regions Infested
 
Click here for a map of Jepson regions

Infested Jepson Regions:
Check the boxes to indicate the Jepson floristic provinces in which this species is found.














Addendum L - External Links & Resources

Cal-IPC Plant Profile
The Cal-IPC Plant Profile for this species.
http://www.cal-ipc.org/ip/management/plant_profiles/Arctotheca_calendula.php
Calflora Plant Profile:
The Calflora Plant Profile for this species.
http://www.calflora.org/cgi-bin/species_query.cgi?where-calrecnum=11138
CalWeedMapper:
Load CalWeedMapper with this species already selected.
http://calweedmapper.cal-ipc.org/maps/?species=52