Plant Assessment Form

Phoenix canariensis

Common Names: Canary Island date palm

Evaluated on: 1/6/05

List committee review date: 08/07/2005

Re-evaluation date:

Evaluator(s)

Elizabeth Brusati, project manager
California Invasive Plant Council
1442A Walnut St. #462, Berkeley, CA 94709
510-843-3902
edbrusati@cal-ipc.org
Joseph M. DiTomaso
University of California, Davis
Dept. Plant Sci., Mail Stop 4, Davis, CA 95616
530-754-8715
jmditomaso@ucdavis.edu

List commitee members

Jake Sigg
Peter Warner
Bob Case
John Knapp
Elizabeth Brusati

General Comments

No general comments for this species

Table 2. Criteria, Section, and Overall Scores

Overall Score? Limited
Alert Status? No Alert
Documentation? 2.5 out of 5
Score Documentation
1.1 ?Impact on abiotic ecosystem processes C Observational
Impact?
Four-part score CCUD Total Score
C
1.2 ?Impact on plant community C. Minor Observational
1.3 ?Impact on higher trophic levels U. Unknown
1.4 ?Impact on genetic integrity D. None Other Published Material
2.1 ?Role of anthropogenic and natural disturbance in establishment B. Moderate Other Published Material
Invasiveness?
Total Points
13 Total Score B
2.2 ?Local rate of spread with no management B. Increases less rapidly Observational
2.3 ?Recent trend in total area infested within state B. Increasing less rapidly Observational
2.4 ?Innate reproductive potential
(see Worksheet A)
C. Low Other Published Material
2.5 ?Potential for human-caused dispersal B. Moderate Other Published Material
2.6 ? Potential for natural long-distance dispersal A. Frequent Other Published Material
2.7 ?Other regions invaded C. Already invaded Other Published Material
3.1 ?Ecological amplitude/Range
(see Worksheet C)
D. Narrow Other Published Material
Distribution?
Total Score D
3.2 ?Distribution/Peak frequency
(see Worksheet C)
D. Very low Anecdotal

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? C Observational
Identify ecosystem processes impacted:

At one location in southern California, invasion of palm trees (Phoenix and Washingtonia) caused the river to change direction, flooding an historical site (1). Seeds may be allelopathic, but unknown if this effect is persistent.. Scoring as C because this is only an observation from one site and we don't know how much of the change was due to Phoenix vs. Washingtonia invasion.


Sources of information:

1. Personal communication from Cindy Burrascano, California Native Plant Society. E-mail in Cal-IPC files.
2. Personal observations, John Knapp, Catalina Island Conservancy, Avalon, CA


Question 1.2 Impact on plant community composition,
structure, and interactions?
C Observational
Identify type of impact or alteration:

Displaces native trees. Dense in Los Penasquitos Preserve. Has been the focus of several restoration projects there. Documented as a pest on the San Diego River (1). One adult can produce a carpet of seedlings (2).


Sources of information:

1. Personal communication from Cindy Burrascano, California Native Plant Society. E-mail in Cal-IPC files
2. Personal observations, John Knapp, Catalina Island Conservancy, Avalon, CA.


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

Sharp spines can injure people (1). If it's displacing native trees, presumably it is having an impact on native wildlife as well, but we have no specific information on this.


Sources of information:

1. Floridata website. Phoenix canariensis. http://www.floridata.com/ref/P/phoe_can.cfm


Question 1.4 Impact on genetic integrity? D Other Published Material

none No native Phoenix species.


Sources of information:

Hickman, J. C. (ed.) 1993. The Jepson Manual, Higher Plants of California. University of California Press. Berkeley, CA enter text here


Section 2: Invasiveness
Question 2.1 Role of anthropogenic and natural disturbance
in establishment?
B Observational
Describe role of disturbance:

Grows in full sun, so may need disturbance to open up vegetation (1). Invades riparian areas that are naturally disturbed because they operate under a flood dynamic (2).


Sources of information:

Gilman, E. F., and D. G. Watson. 1994. Phoenix canariensis. Canary Island Date Palm. Fact sheet. ST-439. Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL. Available: http://hort.ifas.ufl.edu/PHOCANA.pdf
2. Personal communication from Cindy Burrascano, California Native Plant Society. E-mail in Cal-IPC files.


Question 2.2 Local rate of spread with no management? B Observational
Describe rate of spread:

Spreading in southern California.


Sources of information:

Personal communication from Cindy Burrascano, California Native Plant Society. E-mail in Cal-IPC files.


Question 2.3 Recent trend in total area infested within state? B Observational
Describe trend:

Spreading in southern California.


Sources of information:

Personal communication from Cindy Burrascano, California Native Plant Society. E-mail in Cal-IPC files.


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

Reproduces by seed. Male and female flowers develop on separate trees (1).


Sources of information:

DiTomaso, J. and E. Healy. 2006. Weeds of California. UC DANR Publ. #3488.


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

Escape from landscape planting via dispersal in water or by birds. Seeds carried by winter rains into storm drains and then to creeks and rivers (1). Planted in parks and gardens or along streets (2).


Sources of information:

1. DiTomaso, J. and E. Healy. 2006. Weeds of California. UC DANR Publ. #3488.
2. Brenzel, K. N. 2001. Sunset Western Garden Book. Sunset Publishing Company, Menlo Park, CA.


Question 2.6 Potential for natural long-distance dispersal? A Other Published Material
Identify dispersal mechanisms:

Seeds dispersed by birds. Seeds are large and can be carried downstream in creeks and rivers (1, 2).


Sources of information:

1. DiTomaso, J. and E. Healy. 2006. Weeds of California. UC DANR Publ. #3488.
2. Personal communication from Cindy Burrascano, California Native Plant Society. E-mail in Cal-IPC files..


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

Native to Canary Islands. Naturalized in Florida (1). Native habitat includes riparian areas.


Sources of information:

DiTomaso, J. and E. Healy. 2006. Weeds of California. UC DANR Publ. #3488.


Section 3: Distribution
Question 3.1 Ecological amplitude/Range? D Other Published Material

Naturalized in Sonoma, Glenn, San Luis Obispo, and San Diego counties (1). Most common in southern California. Has become a problem in riparian corridors (2, 3). Hardy to 20 degrees F. Sunset lists it as appropriate for zones 9, 12-24 (4). Can tolerate salt spray (4). Listed as an exotic tree for which mechanized removal is authorized by the US Army Corps of Engineers (6).


Sources of information:

1. USDA, NRCS. 2004. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA
2. DiTomaso, J. and E. Healy. 2006. Weeds of California. UC DANR Publ. #3488.
3. Personal communication from Cindy Burrascano, California Native Plant Society. E-mail in Cal-IPC files.
4. Brenzel, K. N. 2001. Sunset Western Garden Book. Sunset Publishing Company, Menlo Park, CA.
5. Gilman and Watson 1994
6. USACE. 2003. Special public notice. Regional general permit No. 41: Removal of invasive exotic plants. US Army Corps of Engineers, Los Angeles District. Public notice 200301094-JMB. Available: http://www.spl.usace.army.mil/regulatory/rgp41_pn.pdf


Question 3.2 Distribution/Peak frequency? D Anecdotal
Describe distribution:

Mainly found in wildlands of Southern California


Sources of information:

Worksheet A - Innate reproductive potential

Reaches reproductive maturity in 2 years or less No
Dense infestations produce >1,000 viable seed per square meter No
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 Unknown
Viable seed produced with both self-pollination and cross-pollination No
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: 2
Total unknowns: 1
Total score: C?

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 scrub
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, Meadows, and other Herb Communitiescoastal prairie
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 woodlandD, < 5%
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): D
Distribution (highest score): D

Infested Jepson Regions

Click here for a map of Jepson regions

  • Cascade Range
  • Central West
  • Great Valley
  • Northwest
  • Southwest
  • Sonoran Desert