Plant Assessment Form

Genista linifolia

Evaluated on: 2/28/03

List committee review date: 24/01/2008

Re-evaluation date: 01/17/2017

Evaluator(s)

John Knapp/California Islands Ecologist
The Nature Conservancy
jknapp@tnc.org
Mona Robison/Science Program Manager / JULIA PARISH PLANT CONSERVATION MANAGER
Cal-IPC / CIC
916-802-2004 / 310 510-1299 X229
rrobison@cal-ipc.org

List committee members

Joe DiTomaso
Cynthia Roye
Peter Warner
Joanna Clines
Mike Kelly

General Comments

PAF was reviewed by committee in 2008 and not finished at that time. Re-evaluated in 2017 with new information.

Currently a serious problem on Catalina Island. Has been reported from mainland but status and locations of those populations unknown. Will be re-evaluated if populations establish on mainland. Native origin- Western Mediterranean: Canary Islands, Morroco, Algeria, southern Spain and France.

Due to its limited distribution and abundance in California, very little research has been conducted on G. linifolia, therefore, research conducted on the closely related G. monspessulana was used to fill in the gaps of lacking information for G. linifolia. G. linifolia overlaps with G. monspessulana; however, G. monspessulana has a greater native range than G. linifolia

Table 2. Criteria, Section, and Overall Scores

Overall Score? Moderate
Alert Status? No Alert
Documentation? 3 out of 5
Score Documentation
1.1 ?Impact on abiotic ecosystem processes B Reviewed Scientific Publication
Impact?
Four-part score BBUD Total Score
B
1.2 ?Impact on plant community B. Moderate Other Published Material
1.3 ?Impact on higher trophic levels U. Unknown 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
15 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 Other Published Material
2.4 ?Innate reproductive potential
(see Worksheet A)
A. High Other Published Material
2.5 ?Potential for human-caused dispersal B. Moderate Other Published Material
2.6 ? Potential for natural long-distance dispersal C. Rare 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)
D. Very 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? B Reviewed Scientific Publication
Identify ecosystem processes impacted:

G. linifolia alters fire regimes by burning readily, increasing fire frequency and intensity (1,2,4 & 5-G. monspessulana). Alters nutrient and water cycling in Spain (3). G. linifolia increased fire intensity of coastal scrub during the 2007 Island Fire on Catalina Island (6). Dense even aged stands, carries flame to overstory native plants (6).


Sources of information:

(1) Carroll, M.C., L.L. Laughrin, and A.C. Bromfield. 1999. Fire on the California islands: does it play a role in chaparral and closed-cone pine forest habitats? Pp. 3-87 in: F.G. Hochberg (ed.). Proceedings of the third California islands symposium. Santa Barbara, California: Santa Barbara Natural History Museum.
(2) Mastro, L.W. 1993. A study on the natural history of Cytisus on Santa Catalina Island with an emphasis on biological control. in: F.G. Hochberg (ed.). Proceedings of the third California islands symposium. Santa Barbara, California: Santa Barbara Natural History Museum.
(3) Gonzalez-Andres, F. and J.M. Ortiz. 1999. Specificity of rhizobia nodulating Genista monspessulana and Genista linifolia in vitro and in field situations. Arid Soil Research and Rehabilitation 13(3): 223-237.
(4) Anonymous. 2001. A comprehensive broom and gorse biological control effort. CalEPPC News 9(2): 3-6.
(5) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press.
(6) Knapp, J. J. Personal observation on Catalina Island during 2007 Island Fire.


Question 1.2 Impact on plant community composition,
structure, and interactions?
B Other Published Material
Identify type of impact or alteration:

G. linifolia destroys community integrity (1). Out competes native vegetation even on infertile soils (2-G. monspessulana, 3, 5). Displaces native flora (2-G. monspessulana, 3). Forms dense monostands (2-G. monspessulana, 3,4) that commonly reach 100% cover and extripate populations of native species (3). G. linifolia grows rapidly (2-G. monspessulana, 3) and shades out native species (2-G. monspessulana, 3). G. linifolia grows in close proximity to several listed and endemic plant species and in riparian habitat of listed wildlife species on Catalalina Island (3). G. linifolia alters island chaparral, island woodland, and oakwoodland understory by creating a thick wall of vegetation from the ground to canopy (3). Mutualistic relationship with nitrogen-fixing bacteria found in small nodules on roots (2). Fire dervived increase in the root:above-ground biomass ration allows resprouters to reach higher folia concentrations, even if nutrient uptake efficiency or soil fertility remain unchanged (5).


Sources of information:

1) Mastro, L.W. 1987. Effects of Dyers Greenwold, Cytisus linifolius (Fabaceae) on the native vegetation of Santa Catalina Island. Crossosoma, 13(6):2-6.
(2) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press.
(3) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.
(4) McClintock, E. 1979. The weedy brooms _ where did they come from? Fremontia 6(4): 15-17.
(5) Carreira, J.A. and F.X. Niell. 1992. Plant nutrient changes in a semi-arid Mediterranean shrubland after fire. Journal of Vegetation Science 3(4): 457-466.


Question 1.3 Impact on higher trophic levels? U Other Published Material
Identify type of impact or alteration:

Genista monspessulana can be toxic to livestock if ingested in large quantities but no information on G. linifolia. Dense thickets can inhibit the movement of wildlife (3, 4), including island fox, Catalina quail, and mule deer (5).


Sources of information:

(1) Blood, K. Date unknown. Environmental Weeds: a field guide for SE Australia
(2) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press.
(3) McClintock, E. 1979. The weedy brooms _ where did they come from? Fremontia 6(4): 15-17.
(4) Hoshovsky, M. 1986. Element stewardship abstract: Cytisus scoparius (Scotch broom), Cytisus monspessulanus (French broom), and Spartium junceum (Spanish broom). The Nature Conservancy, Washington, D.C.
(5) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.


Question 1.4 Impact on genetic integrity? D Reviewed Scientific Publication

No hybridization is known to occur. 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?
A Other Published Material
Describe role of disturbance:

Planted as an ornamental in Australia (1) and on Catalina Island (5). Brooms colonize open disturbed sites, roadsides, and pastures, and can invade undisturbed (4) grasslands, coastal scrub, oak woodlands, chaparral, and open forests (2, 5). Game trails (3), road making, pig rooting, fire, vegetative disturbance can lead to establishment (4,5).


Sources of information:

1) Blood, K. Date unknown. Environmental Weeds: a field guide for SE Australia. NE.
(2) Anonymous. 2001. A comprehensive broom and gorse biological control effort. CalEPPC News 9(2): 3-6.
(3) Mastro, L.W. 1990. A study on the natural history of Cytisus (Fabaceae) on Santa Catalina Island with an emphasis on biological control. Masters thesis, California State University Long Beach. Pp. 1-77.
(4) 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.
(5) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.


Question 2.2 Local rate of spread with no management? A Other Published Material
Describe rate of spread:

eeds are dispersed explosively up to 3-4 meters from individual plants by shattering (1,2-G. monspessulana). On Catalina Island, existing populations annually produce tens of thousands of new seedlings, and many young new satelite populations are detected (3). On Catalina Island, one population was discovered as escaped from cultivation in 1923 (4), by 1967 it became abundantly established on the SE half of the Island (5), and in 2003, 824 populations were recorded covering 40,487,825 ft2 (3).


Sources of information:

1) Anonymous. No date. Different fates of island brooms: contrasting evolustion in Adenocarpus, Gensta and Teline (Genisteae, Leguminosae) in the Canary Islands and Madeira. Botanical Journal of the Linnean Society. Pp. 260-278
(2) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press.
(3) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.
(4) Millspaugh, C.F. and Nuttall, L.W. 1923. Flora of Santa Catalina Island. P. 140. Field Museum of Natural History, Botany v.5. Chicago.
(5) Thorne, R.F. 1967. A flora of Santa Catalina Island, California. Aliso, 6(3):1-77.


Question 2.3 Recent trend in total area infested within state? B Other Published Material
Describe trend:

Two known locations in California, Santa Catalina Island (40,487,825 square feet invaded (2)) and Romero Canyon, Santa Barbara County (1). G. linifolia IS THE #1 PRIORITY species controlled on SANTA Catalina Island (2, PARISH, PERS. COMM.), AND SPENDS 50% OF MANAGEMENT RESOURCES CONTROLLING THIS SPECIES, AND OCCUPIES 1,984 ACRES AS OF 2016 COMPRISING 2,547 INFESTATIONS (PARISH, PERS. COMM.)


Sources of information:

(1) Mastro, L.W. 1993. A study on the natural history of Cytisus on Santa Catalina Island with an emphasis on biological control. in: F.G. Hochberg (ed.). Proceedings of the third California islands symposium. Santa Barbara, California: Santa Barbara Natural History Museum.
(2) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.
PARISH, J. 2017. PERSONAL COMMUNICATION.


Question 2.4 Innate reproductive potential? A Other Published Material
Describe key reproductive characteristics:

1) Mastro, L.W. 1993. A study on the natural history of Cytisus on Santa Catalina Island with an emphasis on biological control. in: F.G. Hochberg (ed.). Proceedings of the third California islands symposium. Santa Barbara, California: Santa Barbara Natural History Museum.
(2) Brown, K. and K. Brooks. 2002. Bushland weeds _ a practical guide to their management. Pp. 86-87. Environmental Weeds Action Network. Greenwood, Australia.
(3) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.
(4) Gonzalez-Andres, F. and J.M. Ortiz. 1999. Specificity of rhizobia nodulating Genista monspessulana and Genista linifolia in vitro and in field situations. Arid Soil Research and Rehabilitation 13(3): 223-237.
(5) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press.
(6) Knapp, J.J. 2002. Personal observation.
(7) Steinmaus, S. 2002. Personal communication.
(8) Anonymous. 2001. A comprehensive broom and gorse biological control effort. CalEPPC News 9(2): 3-6.
(9) Mastro, L.W. 1990. A study on the natural history of Cytisus (Fabaceae) on Santa Catalina Island with an emphasis on biological control. Masters thesis, California State University Long Beach. Pp. 1-77.
(10) 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.
(11) Comings, A. 1994. Fighting invaders with bare hands. Fremontia 22(3): 30-31.
(12) Hoshovsky, M. 1986. Element stewardship abstract: Cytisus scoparius (Scotch broom), Cytisus monspessulanus (French broom), and Spartium junceum (Spanish broom). The Nature Conservancy, Washington, D.C.


Sources of information:

Contaminated soil (1,6), road grading equipment, maintenance machinery, and mud (2-G. monspessulana, 3,6). Other brooms are widely planted as ornamentals but G. linifolia is not commonly sold (1,4). Feral animals may disperse G. linifolia seeds (5). Vehicles, footwear, pig rooting and the digestive tracts of horses and other animals, and short-scale dispersal through microsites such as fallen trees and animal tracts (6).


Question 2.5 Potential for human-caused dispersal? B Other Published Material
Identify dispersal mechanisms:

Contaminated soil (1,6), road grading equipment, maintenance machinery, and mud (2-G. monspessulana, 3,6). Other brooms are widely planted as ornamentals but G. linifolia is not commonly sold (1,4). Feral animals may disperse G. linifolia seeds (5). Vehicles, footwear, pig rooting and the digestive tracts of horses and other animals, and short-scale dispersal through microsites such as fallen trees and animal tracts (6).


Sources of information:

(1) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.
(2) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press.
(3) Saldana, H. 2002. Personal communication.
(4) Anonymous. 2001. A comprehensive broom and gorse biological control effort. CalEPPC News 9(2): 3-6.
(5) Mastro, L.W. 1990. A study on the natural history of Cytisus (Fabaceae) on Santa Catalina Island with an emphasis on biological control. Masters thesis, California State University Long Beach. Pp. 1-77.
(6) 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 2.6 Potential for natural long-distance dispersal? C Other Published Material
Identify dispersal mechanisms:

Seeds are transported by birds on the Canary Islands (1,3,4-broom species), and California quail are suspected of dispersing broom seeds (2). Ants, animals, river water and rain wash also disperse seeds (,43-G. monspessulana). Once in a stream bed, G. linifolia has been found further downstream in areas where infestations have never been known to occur (5).
However, most of these vectors are <1km dispersal and therefore do not represent significant means of long-distance spread in California.


Sources of information:

(1) Anonymous. No date. Different fates of island brooms: contrasting evolustion in Adenocarpus, Gensta and Teline (Genisteae, Leguminosae) in the Canary Islands and Madeira. Botanical Journal of the Linnean Society. Pp. 260-278. NEED MORE INFO.
(2) Steinmaus, S. 2002. Personal communication.
(3) Bossard, C.C. 2000. Genista monspessulana. Bossard, C.C., J.M. Randall, and M.C. Hoshovsky, (eds). In, Invasive plants of Californias wildlands. Pp. 203-208. Berkeley, California: University of California Press.
(4) Hoshovsky, M. 1986. Element stewardship abstract: Cytisus scoparius (Scotch broom), Cytisus monspessulanus (French broom), and Spartium junceum (Spanish broom). The Nature Conservancy, Washington, D.C.
(5) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.


Question 2.7 Other regions invaded? C Other Published Material
Identify other regions:

Considered naturalized in Australia in 1887, and then categorized as a noxious weed in 1900 (1,2,3), and is the second most important broom species targeted for biocontrol (4).


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? A Other Published Material

No data on habitats invaded was found for other locations in California other than on Catalina Island (2). G. linifolia was first planted at the Descanso Hotel in the early 1920's, and by 1938 it was considered naturalized on Santa Catalina Island (1). The following is the percentage of habitats invaded on Santa Catalina Island: bare-0.42%, chaparral-1.6%, coastal scrub-0.6%, coastal scrub/grassland-6.7%, grassland-0.01%, riparian-1.02%, nearly 100 populations recorded in non-native communities (2), AND ISLAND WOODLAND (PARISH). 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 grasslands (5), foothill oak woodland (5).


Sources of information:

(1) Mastro, L.W. 1987. Effects of Dyers Greenwold, Cytisus linifolius (Fabaceae) on the native vegetation of Santa Catalina Island. Crossosoma, 13(6):2-6.
(2) Knapp, J.J. 2004. Catalina Island 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 Californias 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) 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? D Other Published Material
Describe distribution:

No data on habitats invaded was found for other locations in California other than on Catalina Island (1).
PARISH, J. 2017. PERSONAL COMMUNICATION.


Sources of information:

(1) Knapp, J.J. 2004. Catalina Island Invasive Plant Ranking Plan for the Catalina Island Conservancy. Unpublished.


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 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: 8
Total unknowns: 1
Total score: A?

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?
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
chaparralD, < 5%
Grasslands, Vernal Pools, Meadows, and other Herb Communitiescoastal prairieD, < 5%
valley and foothill grassland
Great Basin grassland
vernal pool
meadow and seep
alkali playa
pebble plain
Bog and Marshbog and fen
marsh and swamp
Riparian and Bottomland habitatriparian forest
riparian woodland
riparian scrub (incl.desert washes)D, < 5%
Woodlandcismontane woodlandU, Unknown
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): B
Distribution (highest score): D

Infested Jepson Regions

Click here for a map of Jepson regions

  • Northwest
  • Southwest