Plant Assessment Form

Potamogeton crispus

Common Names: curly-leaved pondweed; curled pondweed; curly pondweed

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 DiTomaso
University of California-Davis
Dept. Plant Sci., Mail Stop 4, Davis, CA 95616
530-754-8715
jmditomaso@ucdavis.edu

List commitee members

Joe DiTomaso
Alison Stanton
Joanna Clines
Cynthia Roye
Doug Johnson

General Comments

No general comments for this species

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 BBCU Total Score
B
1.2 ?Impact on plant community B. Moderate Reviewed Scientific Publication
1.3 ?Impact on higher trophic levels C. Minor Reviewed Scientific Publication
1.4 ?Impact on genetic integrity U. Unknown
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 B. Increases less rapidly Other Published Material
2.3 ?Recent trend in total area infested within state C. Stable Other Published Material
2.4 ?Innate reproductive potential
(see Worksheet A)
A. High Reviewed Scientific Publication
2.5 ?Potential for human-caused dispersal B. Moderate Other Published Material
2.6 ? Potential for natural long-distance dispersal A. Frequent Reviewed Scientific Publication
2.7 ?Other regions invaded C. Already invaded Reviewed Scientific Publication
3.1 ?Ecological amplitude/Range
(see Worksheet C)
B. Moderate Reviewed Scientific Publication
Distribution?
Total Score B
3.2 ?Distribution/Peak frequency
(see Worksheet C)
C. 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? B Reviewed Scientific Publication
Identify ecosystem processes impacted:

Dense mats impede water flow. During periods of rapid growth, can deplete nutrients. Does not form infestations as dense as Myriophyllum spicatum or Hydrilla verticillata.


Sources of information:

Catling, P.M., and I. Dobson. 1985. The biology of Canadian weeds. 69. Potamogeton crispus L. Canadian Journal of Plant Sciences. 65:655-668


Question 1.2 Impact on plant community composition,
structure, and interactions?
B Reviewed Scientific Publication
Identify type of impact or alteration:

Can grow in dense stands that cover large areas of the water surface (1), but in California the stands are moderately dense.


Sources of information:

1. Catling, P.M., and I. Dobson. 1985. The biology of Canadian weeds. 69. Potamogeton crispus L. Canadian Journal of Plant Sciences. 65:655-668


Question 1.3 Impact on higher trophic levels? C Reviewed Scientific Publication
Identify type of impact or alteration:

Eaten by dabbling ducks and coots. Depletion of nutrients can harm fish.


Sources of information:

Catling, P.M., and I. Dobson. 1985. The biology of Canadian weeds. 69. Potamogeton crispus L. Canadian Journal of Plant Sciences. 65:655-668


Question 1.4 Impact on genetic integrity? U

There are several native Potamogeton species that hybridize with each other, but as P. crispus reproduces mostly vegetatively, hybridization is probably not common. However, other species of Potamogeton are known to hybridize so it is still possible, although unknown.


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:

Can readily become established in an undisturbed aquatic system.


Sources of information:

DiTomaso, J.M., and E. H. Healy. 2003. Aquatic and Riparian Weeds of the West. University of California, Agriculture and Natural Resources Publication 3421.


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

Fast-growing plant (1). Can spread in new area.


Sources of information:

1. Moore, L. M. 2002. Plant guide: Potamogeton crispus. USDA Natural Resource Conservation Service, National Plant Data Center. Available: http://plants.usda.gov


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

Already widespread in many regions of California.


Sources of information:

DiTomaso, J.M., and E. H. Healy. 2003. Aquatic and Riparian Weeds of the West. University of California, Agriculture and Natural Resources Publication 3421.


Question 2.4 Innate reproductive potential? A Reviewed Scientific Publication
Describe key reproductive characteristics:

Perennial herbaceous submerged aquatic plant. Extent of self-compatibility unknown. Develops fruit in shallow water. Each fruit produces one seed. Germination of seeds is rare. Vegetative reproduction is more common in North America. A single dominant stem apex in California produced over 900 dormant apices between June and October of the same year (1). Flowers May to September (2).


Sources of information:

1. Catling, P.M., and I. Dobson. 1985. The biology of Canadian weeds. 69. Potamogeton crispus L. Canadian Journal of Plant Sciences. 65:655-668
2. DiTomaso, J.M., and E. H. Healy. 2003. Aquatic and Riparian Weeds of the West. University of California, Agriculture and Natural Resources Publication 3421.


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

Could be caught on boats and moved from lake to lake.


Sources of information:

DiTomaso, J.M., and E. H. Healy. 2003. Aquatic and Riparian Weeds of the West. University of California, Agriculture and Natural Resources Publication 3421.


Question 2.6 Potential for natural long-distance dispersal? A Reviewed Scientific Publication
Identify dispersal mechanisms:

Fruits are released underwater, so dispersal is probably by water currents, and maybe waterfowl.


Sources of information:

Catling, P.M., and I. Dobson. 1985. The biology of Canadian weeds. 69. Potamogeton crispus L. Canadian Journal of Plant Sciences. 65:655-668


Question 2.7 Other regions invaded? C Reviewed Scientific Publication
Identify other regions:

Native to Eurasia, Africa, and Australia. Now occurs worldwide, including throughout most of North America (1).


Sources of information:

Catling, P.M., and I. Dobson. 1985. The biology of Canadian weeds. 69. Potamogeton crispus L. Canadian Journal of Plant Sciences. 65:655-668


Section 3: Distribution
Question 3.1 Ecological amplitude/Range? B Reviewed Scientific Publication

Introduced to California before 1900. Occurs in aquatic habitats such as rivers and canals. Restricted to alkaline calcareous waters and is tolerant of slightly brackish waters (1). Also inhabits ponds, lakes, and marshy areas. In California, occurs in North Coast Ranges, Central Coast, Central Valley, San Francisco Bay Region, Central and Eastern Transverse Ranges, South Coast, Channel Islands, and Mojave Desert (2).


Sources of information:

Catling, P.M., and I. Dobson. 1985. The biology of Canadian weeds. 69. Potamogeton crispus L. Canadian Journal of Plant Sciences. 65:655-668
2. DiTomaso, J.M., and E. H. Healy. 2003. Aquatic and Riparian Weeds of the West. University of California, Agriculture and Natural Resources Publication 3421.


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

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 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 No
Viable seed produced with both self-pollination and cross-pollination Unknown
Has quickly spreading vegetative structures (rhizomes, roots, etc.) that may root at nodes Yes
Fragments easily and fragments can become established elsewhere Yes
Resprouts readily when cut, grazed, or burned Yes
Total points: 6
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, reservoirsC, 5% - 20%
Aquatic Systemsrivers, streams, canalsC, 5% - 20%
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 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): B
Distribution (highest score): C

Infested Jepson Regions

Click here for a map of Jepson regions

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