Plant Assessment Form

Conicosia pugioniformis

Synonyms: Mesembryanthemum elongatum

Common Names: narrowleaf iceplant; false iceplant; conicosia

Evaluated on: 4/6/05

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 committee members

Jake Sigg
Peter Warner
Bob Case
John Knapp
Elizabeth Brusati

General Comments

Information needed on dispersal mechanisms.

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 U. Unknown Reviewed Scientific Publication
Impact?
Four-part score UCUD Total Score
C
1.2 ?Impact on plant community C. Minor Other Published Material
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
11 Total Score B
2.2 ?Local rate of spread with no management B. Increases less rapidly Other Published Material
2.3 ?Recent trend in total area infested within state B. Increasing less rapidly Anecdotal
2.4 ?Innate reproductive potential
(see Worksheet A)
A. High Other Published Material
2.5 ?Potential for human-caused dispersal C. Low Anecdotal
2.6 ? Potential for natural long-distance dispersal D. None Observational
2.7 ?Other regions invaded C. Already invaded Other Published Material
3.1 ?Ecological amplitude/Range
(see Worksheet C)
B. Moderate Other Published Material
Distribution?
Total Score C
3.2 ?Distribution/Peak frequency
(see Worksheet C)
D. Very low Observational

Table 3. Documentation

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

Section 1: Impact
Question 1.1 Impact on abiotic ecosystem processes? U Reviewed Scientific Publication
Identify ecosystem processes impacted:

No information Other members of this family are known to alter soil chemistry, but there is no information for Conicosia pugioniformis.


Sources of information:

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

Can cover or be interspersed with other vegetation and can be locally abundant. However, unlike Carpobrotus iceplant, it does not form large clonal mats (1). Can overtake rare native plants on dunes (2). Locally abundant on Tomales Bay, Marin County (3) and in Morro Bay (4).


Sources of information:

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

No information


Sources of information:

Question 1.4 Impact on genetic integrity? D Other Published Material

None No native Conicosia (or Mesembryanthemum) in California


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 Other Published Material
Describe role of disturbance:

Invades areas with natural or anthropogenic disturbance, including open areas in foredunes and maritime chaparral after fire (1). Spreads along roadsides or trails (2).


Sources of information:

1. Albert and D'Antonio 2000
2. Bill Deneen, San Luis Obispo, personal communication. 2/24/05


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

Seeds from dense populations can spread into adjacent areas. Plants can grow to several feet in diameter in a single growing season (1). Observed to be spreading around Tomales Bay, Marin County (2), and on the Guadelupe-Nipomo Dunes in San Luis Obispo (3, 4).


Sources of information:

1. Albert and D'Antonio 2000
2. Gluesenkamp, Dan, biologist, Audubon Canyon Ranch. personal communication 2/24/05
3. Thackery, Wendy, ecologist/botanist, The Land Conservancy of San Luis Obispo. personal communication 2/24/05
4.Denneen, Bill, San Luis Obispo, personal communication, 2/24/05


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

Based on comments in e-mails above, it seems to be spreading. Was not present at Nipomo Dunes twenty years ago, but has become a significant problem since then. The USDA PLANTS database (http://plants.usda.gov) lists it only in Santa Barbara county, but obviously it has spread beyond that.


Sources of information:

1. Thackery, Wendy, ecologist/botanist, The Land Conservancy of San Luis Obispo. personal communication 2/24/05
2. Denneen, Bill, San Luis Obispo, personal communication, 2/24/05


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

Short-lived succulent. Fruit is cone-shaped capsule that splits open when drying and is easily dispersed by wind, spilling seeds as it tumbles. Individual capsules produce tens to hundreds of seeds. Unlike Carpobrotus iceplant, Conicosia does not root along trailing shoots. No spread by vegetative propagules. Plants flower in summer or fall of their first or second year and every subsequent year. Evergreen shoots may grow year-round. Plants can resprout from the buried root crown after aboveground tissue is removed.


Sources of information:

Albert and D'Antonio 2000


Question 2.5 Potential for human-caused dispersal? C Anecdotal
Identify dispersal mechanisms:

Spreads along roadsides or trails (1), so seeds could be spread by human either directly by seed capsule sticking to clothing or indirectly by paths in the dunes. Means of dispersal unclear.


Sources of information:

1. Denneen, Bill, San Luis Obispo, personal communication, 2/24/05


Question 2.6 Potential for natural long-distance dispersal? D Observational
Identify dispersal mechanisms:

Fruit is cone-shaped capsule that splits open when drying and can be dispersed by wind, spilling seeds as it tumbles. However, most seed simply fall at the base of parent plant and wind would not move seed 1 km. Unknown how far the seed is able to be carried.


Sources of information:

DiTomaso, observational
Albert and D'Antonio 2000


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

Native to South Africa. Probably introduced to US as an ornamental in the early 1900's. Scoring as C because it already invades a range of habitats in California.


Sources of information:

Albert and D'Antonio 2000


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

Found from Point Reyes Peninsula (1) to Point Conception (2). Has only recently (1980's) been recognized as an important component of California coastal habitats. In California, generally found on coastal dunes and bluff scrub, but possibly could invade coastal scrub, coastal prairie, and maritime chaparral. Seems to require well-drained, sandy soil (2).


Sources of information:

1. Gluesenkamp, Dan, biologist, Audubon Canyon Ranch. personal communication 2/24/05
2. Albert and D'Antonio 2000


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

Not very common in California.


Sources of information:

DiTomaso, observational.


Worksheet A - Innate reproductive potential

Reaches reproductive maturity in 2 years or less Yes
Dense infestations produce >1,000 viable seed per square meter Yes
Populations of this species produce seeds every year. Yes
Seed production sustained over 3 or more months within a population annually No
Seeds remain viable in soil for three or more years Unknown
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 Yes
Resprouts readily when cut, grazed, or burned Yes
Total points: 7
Total unknowns: 2
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
DunescoastalD, < 5%
desert
interior
Scrub and Chaparralcoastal bluff scrubD, < 5%
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 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): B
Distribution (highest score): D

Infested Jepson Regions

Click here for a map of Jepson regions

  • Central West
  • Northwest