Plant Assessment Form

More Genista monspessulana resources

Genista monspessulana

Synonyms: Cytisus monpsessulana, C. racemosus, C. canariensis, Gensita monspessulana, Teline monspessulana

Common Names: French broom; soft broom; canary broom; Montepellier broom

Evaluated on: 6/8/04

List committee review date: 11/03/2005

Re-evaluation date:

Evaluator(s)

John J. Knapp/ Invasive Plant Program Manager
Catatlina Island Conservancy
P.O. Box 2739 Avalon, CA 90704
(310) 510-1299
jknapp@catalinaconservancy.org

List committee members

Joe DiTomaso
John Randall
Carla Bossard

General Comments

No general comments for this species

Table 2. Criteria, Section, and Overall Scores

Overall Score? High

Alert Status? No Alert

Documentation? 3 out of 5

Score

Documentation

1.1

?Impact on abiotic ecosystem processes

A. Severe

Reviewed Scientific Publication

Impact?
Four-part score AAAD Total Score
A

1.2

?Impact on plant community

A. Severe

Other Published Material

1.3

?Impact on higher trophic levels

A. Severe

Other Published Material

1.4

?Impact on genetic integrity

D. None

Reviewed Scientific Publication

2.1

?Role of anthropogenic and natural disturbance in establishment

A. Severe

Other Published Material

Invasiveness?
Total Points
18 Total Score A

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

A. Increasing rapidly

Other Published Material

2.4

?Innate reproductive potential
(see Worksheet A)

A. High

Other Published Material

2.5

?Potential for human-caused dispersal

A. High

Other Published Material

2.6

? Potential for natural long-distance dispersal

B. Occasional

Other Published Material

2.7

?Other regions invaded

C. Already invaded

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)

C. Low

Other Published Material

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.	A Reviewed Scientific Publication
Identify ecosystem processes impacted: G. monspessulana alters fire regimes by buning readily, increasing fire frequency and intensity (1,2). Alters nutrient and water cycling in Spain (3) and California (4. 5). Dense even aged stands, carries flame to overstory native plants. Nitrogen fixer, increases probability of invasion by other plants. Sources of information:
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 Other Published Material
Identify type of impact or alteration: Out competes native vegetation even on infertile soils (2,4). Displaces native flora (2). Forms dense monostands (1,2,3) that commonly reach 100% cover and extripate populations of native species (3). G. monspessulana grows rapidly (2) and shades out native species (2,3). G. monspessulana grows in close proximity to several listed and endemic plant species and in riparian habitat of listed wildlife species on Catalalina Island (3). Mutualistic relationship with nitrogen-fixing bacteria found in small nodules on roots (2). Fire dervived increase of the root:above-ground biomass ratio allows resprouters to reach higher foliage concentrations, even if nutrient uptake efficiency or soil fertility remain unchanged (4). Sources of information:
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 Other Published Material
Identify type of impact or alteration: Seeds are highly toxic to humans and wildlife (2). Young foliage can cause digestive disorders in horses, and staggering and paralysis in livestock (bison?) (2). Infestations degrade the quality of habitat for wildlife by displacing native forage species and changing microclimate conditions at soil levels, and reduce arthropod populations by 1/3 (as reported in Golden Gate National Recreation Area) (2). Dense thickets can inhibit the movement of wildlife (3), including quail and deer (1). Sources of information:
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 Reviewed Scientific Publication
No hybridization is known to occur with native California taxa. No native California taxa are in the genus Genista. Sources of information: Hickman, J.C. (ed.). 1993. The Jepson manual of higher plants of California. P. 609. University of California Press, Berkeley.
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: Brooms colonize open disturbed sites, roadsides, and pastures, and riparian areas, and can invade undisturbed (2) grasslands, coastal scrub, oak woodlands, and open forests (1). Road construction, pig rooting, fire, and vegetative disturbance facilitate its establishment (2). Sources of information: (1) Anonymous. 2001. A comprehensive broom and gorse biological control effort. CalEPPC News 9(2): 3-6. (2) Anonymous. 2002. Broom: Montpellier broom (Genista monspessulana L.) and English broom (Cytisus scoparius L.). Department of Primary Industries, Water and Environment. http://www.dpiwe.tas.gov.au/inter.nsf/WebPages/RPIO-4ZZ72G?open.
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: Seeds are dispersed explosively up to 3-4 meters from individual plants by shattering (1,2). On Catalina Island, existing populations were surrounded by hundreds of new seedlings, and several young new satelite populations were detected (3). First recorded on Catalina Island in 1967 as infrequent (4), and by 2003 1,915,700 ft2 were invaded (3). Expanded 1.4m/year at Jackson State Demonstration Forest, CA (5). Sources of information:
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	A Other Published Material
Describe trend: At least 23 counties are invaded in California, along the coast from Del Norte to San Diego county, and inland in Butte, Yuba, Nevada, Placer, Sacramento and San Bernadino counties (4). Tamalpais State Park in Marin County targeted for removal (1), Catalina Island targeted for removal (2), Jackson Demonstration State Forest tested control methods (3), Golden Gate National Recreation Area targeted for removal (5), Marin County Open Space District preserve- Alto Bowl targeted for removal (5). Broom species including G. monspessulana have been identified as the second most problem weed by Weed Management Area managers (6). Elkhorn Slough National Estuarine Research Reserve- controlled (7). California State Parks- Inland Empire (8). On Santa Catalina Island, 1,915,700 ft2 are invaded (2). Is not spreading as fast as other broom species because has already invaded most potential habitats. Sources of information:
Question 2.4 Innate reproductive potential? Assess the innate reproductive potential of this species. Worksheet A is provided for computing the score.	A Other Published Material
Describe key reproductive characteristics: Perennial shrub with deep tap root that reproduces by seed (3), but has been propagated by cuttings (2). Fire stimulates prolific germination (?). Reproductive stage reached by two years (3). Medium sized plants of can produce 8,000 seeds per year and have long-lived seed banks, and become reproductive by 2-3 years (4). Seeds can remain viable in the soil for over 5 years, and plants live between 10-15 years (4,5). Resprouts readily after being cut and sometimes after fire (5). Self-pollination has been successful under experiments (6). Sources of information:
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.	A Other Published Material
Identify dispersal mechanisms: Soil contaminated with seed (1,3), road grading equipment, maintenance machinery, and mud (2,3). Brooms are widely planted as ornamentals (1,4). Vehicles, footwear, pig rooting and the digestive tracts of horses and other animals, and microsites such as: fallen trees and animal tracts facilitate establishment and dispersal (3). Lumber activities are a major cause of spread, as seeds are spread along lumber roads and fall down slopes from clear cuts (5). Sources of information:
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 Other Published Material
Identify dispersal mechanisms: Seeds are transported by birds on the Canary Islands (1,3,4), and California quail are suspected of dispersing broom seeds short distances (2). River water also disperse seeds but this species does not grow near water in California (3,4). Seeds do not survive digestion by California quail (5). Sources of information:
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.	C Other Published Material
Identify other regions: Considered naturalized in Australia (1,2,3), and is the most important broom species targeted for biocontrol (4). Also naturalized in New Zealand. Sources of information: (1) Blood, K. Date unknown. Environmental Weeds: a field guide for SE Australia. (2) Harden, G.J. (ed.). 1990. Flora of New South Wales, Vol. 2. New South Wales University Press: Kensington, Australia. (3) Panetta, F.D., Groves, R.H. and Shepherd, R.C. 1998. The biology of Australian Weeds, Vol. 2. R.G. and F.J. Richardson: Meredith, Australia. (4) Syrett, P., Fowler, S.V., Coombs, E.M., Hosking, J.R., Markin, G.P., Paynter, Q.E. and Sheppard, A.W. 1999. The potential for biological control of Scotch broom (Cytisus scoparius) (Fabaceae) and related weedy species. Biocontrol News and Information, 20(1):17-33.
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
G. monspessulana was first introduced to California in 1871 and reported naturalized by the 1940's (1,5). On Santa Catalina Island, 85 populations were recorded and the following is the percentage of habitats invaded: bare-<0.00%, coastal scrub-<0.00%, coastal scrub/grassland-1.6%, grassland-0.16%, chaparral-0.02%, riparian-0.08%, and 13 populations wee recorded in non-native communities (2). G. monspessulana invades coastal plains, mountain slopes, grasslands, and open canopy forests, and disturbed places such as: river banks, road cuts, and forest clear cuts (3). G. monspessulana also invades coast live oak (4), valley grassland (6), foothill oak woodland (6). Sources of information: (1) Mastro, L.W. 1987. Effects of Dyers Greenwold, Cytisus linifolius (Fabaceae) on the native vegetation of Santa Catalina Island. Crossosoma, 13(6):2-6. (2) Knapp, J.J. 2004. Catalina Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished. (3) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press. (4) Archbald, G. 1994. A French broom control method. CalEPPC News. 2(1): 4-6. (5) Alexander, J.M. and C.M. DAntonio. 2003. Control methods for the removal of french and scotch broom tested in coastal California. Ecological Restoration 21(3): 191-198. (6) Schwartz, M.W., Porter, D.J., Randall, J.M. and Lyons, K.E. 1996. Impact of nonindigenous plants. Sierra Nevada Ecosystem Project: Final report to Congress, vol. II, Assessments and scientific basis for management options. Davis: University of California, Centers for Water and Wildland Resources. Pp.1203-1226.
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.	C Other Published Material
Describe distribution: See 3.1. Sources of information: (1) Mastro, L.W. 1987. Effects of Dyers Greenwold, Cytisus linifolius (Fabaceae) on the native vegetation of Santa Catalina Island. Crossosoma, 13(6):2-6. (2) Knapp, J.J. 2004. Catalina Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished. (3) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press. (4) Archbald, G. 1994. A French broom control method. CalEPPC News. 2(1): 4-6. (5) Alexander, J.M. and C.M. DAntonio. 2003. Control methods for the removal of french and scotch broom tested in coastal California. Ecological Restoration 21(3): 191-198. (6) Schwartz, M.W., Porter, D.J., Randall, J.M. and Lyons, K.E. 1996. Impact of nonindigenous plants. Sierra Nevada Ecosystem Project: Final report to Congress, vol. II, Assessments and scientific basis for management options. Davis: University of California, Centers for Water and Wildland Resources. Pp.1203-1226. (7) Thorne, R.F. 1967. A flora of Santa Catalina Island, California. Aliso, 6(3):1-77.

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	Yes
Seeds remain viable in soil for three or more years	Yes
Viable seed produced with both self-pollination and cross-pollination	Yes
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:	9
Total unknowns:	0
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	C, 5% - 20%
	Sonoran desert scrub
	Mojavean desert scrub (incl. Joshua tree woodland)
	Great Basin scrub
	chenopod scrub
	montane dwarf scrub
	Upper Sonoran subshrub scrub
	chaparral	D, < 5%
Grasslands, Vernal Pools, Meadows, and other Herb Communities	coastal prairie	D, < 5%
	valley and foothill grassland	D, < 5%
	Great Basin grassland
	vernal pool
	meadow and seep
	alkali playa
	pebble plain
Bog and Marsh	bog and fen
Bog and Marsh	marsh and swamp
Riparian and Bottomland habitat	riparian forest
	riparian woodland	D, < 5%
	riparian scrub (incl.desert washes)	D, < 5%
Woodland	cismontane woodland	D, < 5%
	piñon and juniper woodland
	Sonoran thorn woodland
Forest	broadleaved upland forest	D, < 5%
	North Coast coniferous forest	C, 5% - 20%
	closed cone coniferous forest
	lower montane coniferous forest
	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):	C

Infested Jepson Regions

Click here for a map of Jepson regions

Cascade Range
Central West
Great Valley
Northwest
Sierra Nevada
Southwest
Modoc Plateau
Sonoran Desert

California Invasive Plant Council

Protecting California’s environment and economy from invasive plants

Plant Assessment Form

More Genista monspessulana resources

Genista monspessulana

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