Plant Assessment Form

Dipsacus sativus

Synonyms: In most of the literature used in this review, the teasels were described as a group, making very little distinction between D. sativus, D. fullonum, and D. sylvestris (name also used for D. fullonum); therefore information is largely identical. Further, according to personal observation by J.M. DiTomaso, in California, both D. fullonum and D. sativus occur in similar habitats and behave in a similar manner.

Common Names: Fullers teasel

Evaluated on: 23-Jul-04

List committee review date: 27/08/2004

Re-evaluation date:

Evaluator(s)

Carri Pirosko
California Department of Food and Agriculture, Noxious Weed Program
20235 Charlanne Drive, Redding, CA 96002
530-545-9119
cpirosko@cdfa.ca.gov
Joseph M. DiTomaso
University of California
Weed Science Program, Robbins Hall, Davis, CA 95616
530-754-8715
ditomaso@vegmail.ucdavis.edu

List commitee members

Peter Warner
Joe DiTomaso
Alison Stanton
John Randall
Jake Sigg
Cynthia Roye

General Comments

No general comments for this species

Table 2. Criteria, Section, and Overall Scores

Overall Score? Moderate
Alert Status? No Alert
Documentation? 4 out of 5
Score Documentation
1.1 ?Impact on abiotic ecosystem processes C Reviewed Scientific Publication
Impact?
Four-part score CBCD 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 D. None Reviewed Scientific Publication
2.1 ?Role of anthropogenic and natural disturbance in establishment B. Moderate Reviewed Scientific Publication
Invasiveness?
Total Points
12 Total Score B
2.2 ?Local rate of spread with no management B. Increases less rapidly Reviewed Scientific Publication
2.3 ?Recent trend in total area infested within state C. Stable Observational
2.4 ?Innate reproductive potential
(see Worksheet A)
B. Moderate Reviewed Scientific Publication
2.5 ?Potential for human-caused dispersal A. High Reviewed Scientific Publication
2.6 ? Potential for natural long-distance dispersal C. Rare Reviewed Scientific Publication
2.7 ?Other regions invaded C. Already invaded Reviewed Scientific Publication
3.1 ?Ecological amplitude/Range
(see Worksheet C)
A. Widespread Reviewed Scientific Publication
Distribution?
Total Score B
3.2 ?Distribution/Peak frequency
(see Worksheet C)
C. Low Reviewed Scientific Publication

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 Reviewed Scientific Publication
Identify ecosystem processes impacted:

light availability, nutrient impacts from persisting stalks/leaves dead stems and flower heads can persist for a year or more, impacting light levels at ground level, shading out native or desirable plant species


Sources of information:

DiTomaso, J.M. and E. Healy. Weeds of California and Other Western States, as yet published.


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

can form dominant stands/monocultures, has impacted threatened species in other states, can form dense and persisting litter/thatch layer Dead stems and flower heads can persist for a year or more, impacting light levels at ground level, shading out native or desirable plant species ;
Mechanisms of competition for individual plants include the wide, horizontally-oriented reosette leaves which proudce heavy shading, and the deep taproot which extends to depths beyond roots of many grasses
Grass litter, and the presence of other dicotyledonous species, and the overall primary productivity of the rest of the community are important factors determining the success or failure of an attempeted colonization by teasel.
If left unchecked, teasel quickly can form large monocultures excluding all native vegetation;
Threatens to displace native species of sensitive conservation status in the UK; invading high quality natural communities including prairies, savannas, seeps and sedge meadows;
One of few plants to have been investigated in detail as an alien species threatening to displace a native plant of sensitive conservation status/listed as Federally threatened (Cirsium vinaceum) in Central New Mexico


Sources of information:

DiTomaso, J.M. and E. Healy. Weeds of California and Other Western States, as yet published; Cheesman, O.D., 1998. The impact of some field boundary management practices development of Dipsacus fullonum L. flowering stems, and implications for conservation. Agriculture, Ecosystems and Environment 68 (1998) 41-49; Werner, P.A., 1975. The biology of Canadian weeds. Can. J. Plant Sci. 55:783-794; Glass, William, 1990. Vegetation management Manual: Cutleved teasel and common teasel, Illinois Nature Preserves Commission, Springfield Illinois.


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

Only one reference found to impacts to cattle and humans trying to pass through a densely infested teasel area stands become dense and impenetrable to humans or livestock;


Sources of information:

Werner, P.A., 1975. The biology of Canadian weeds. Can. J. Plant Sci. 55:783-794


Question 1.4 Impact on genetic integrity? D Reviewed Scientific Publication

Rated as "minor" because the potential does exist according to the literature, see cited reference below. No native species of Dipsacus in California, so hybridization is not relevant. No hybrids involving this species have been described; however, since isolation of species of Dipsacus is mainly geographic and ecological, it is probable that extensive hydridization could be expected when species do come in contact.


Sources of information:

Ehrendorfer, F., 1965. Dispersal mechanisms, genetic systems, and colonizing abilities in some flwering plant families. Pages 331-352 in H.G Baker and G.L. Stebbins, eds. The genetics of colonizing species. Academic Press, New York.


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

Usually establishment requires either anthropogenic or natural disturbance. Usually establishment requires either anthropogenic or natural disturbance.
Teasel sometimes occurs in high quality prairies, savannaas, seeps, and sedge meadows, BUT roadsides, dumps, and heavily disturbed areas are the most common habitats of teasel.


Sources of information:

Glass, William, 1990. Vegetation management Manual: Cutleved teasel and common teasel, Illinois Nature Preserves Commission, Springfield Illinois.


Question 2.2 Local rate of spread with no management? B Reviewed Scientific Publication
Describe rate of spread:

Based on literature cited below, teasel likely rankes some where inbetween "increases, but less rapidly" to "stable". Populations of teasel have been collected from the same field and roadsides for up to 25 years, explanations for the logevity of the population on one site are lacking.
It is suspected that teasel numbers fluctuate greatly and the spread of a population is relatevely slow compared to other weeds because the generation time of teasel is longer than 1 year and there is no vegetative reproduction


Sources of information:

Werner, P.A., 1975. The biology of Canadian weeds. Can. J. Plant Sci. 55:783-794.


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

Statewide, teasel likely rankes some where inbetween "increases, but less rapidly" to "stable". Over the entire state it probably has not expanded its range in the past several years. Personal observation: teasel infestations in roadside meadows have expanded greatly within a 2-3 year timeframe; while some seem to be fairly stable in overall range/expansion potential.
Teasel has spread rapidly in the last 20-30 years- this rapid range expansion probably was aided by construction of the interstate highway system ; because of teasel's use as a horticulture plant, this has aided in its dispersal


Sources of information:

Personal Observation - C. Pirosko and J.M. DiTomaso


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

a single plant might be expected to produce approx. 3,000 seeds;
In fields presenting optimal conditions, teasel rosettes may grow rapidly and flower in their 2nd year, while in less suitable areas the rosettes grow more slowly and populations may consist of plants on a 3- or 4- year reproductive cycle;


Sources of information:

Werner, P.A., 1975. The biology of Canadian weeds. Can. J. Plant Sci. 55:783-794; Glass, William, 1990. Vegetation management Manual: Cutleved teasel and common teasel, Illinois Nature Preserves Commission, Springfield Illinois.


Question 2.5 Potential for human-caused dispersal? A Reviewed Scientific Publication
Identify dispersal mechanisms:

roadside contructions/maintenance; horticulture/nursery trade; dried flower arrangements and gardening Can be dispersed to greater distances with water, mud, soil movement, human activities, and possibly animals; often found along steep roadside banks of new highways where potential for severe erosion is high, connected with highway construction.
Popular in dried flower arrangements and thus could be spread by persons collecting plants for such dried arrangements; because of teasel's use as a horticulture plant, this has aided in its dispersal.


Sources of information:

DiTomaso, J.M. and E. Healy. 2005. Weeds of California and Other Western States, (in press)


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

Most seed do not travel long distances- while, water is the primary mode of long distance dispersal, seeds designed to endure submersion in water for long periods of time Most seed fall near plant base (99.9%), but can be dispersed to greater distances with water, mud, soil movement, human activities, and possibly animals; seeds can float in water up to 22 days without loss of viability; .


Sources of information:

DiTomaso, J.M. and E. Healy. Weeds of California and Other Western States, as yet published. Werner, P.A., 1975. The biology of Canadian weeds. Can. J. Plant Sci. 55:783-794; Glass, William, 1990. Vegetation management Manual: Cutleved teasel and common teasel, Illinois Nature Preserves Commission, Springfield Illinois.


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

Seems to invade similar ecological types in California as in other states and regions North Coast, Klamath Ranges, central and southern Sierra Nevada foothills, San Francisco Bay region, 10 1700m. Most contiguous states, except some southern and north-central states; Very dense patches found in northeastern US and northwestern US;
Currently invades: fallow fields, pastures, roadside, waste places, ditches, riparian sites and other disturbed sties; invading high quality natural communities including prairies, savannas, seeps and sedge meadows


Sources of information:

DiTomaso, J.M. and E. Healy. Weeds of California and Other Western States, as yet published.


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

It looks to invade in seven ecological types, widespread. Currently invades: fallow fields, pastures, roadside, waste places, ditches, riparian sites and other disturbed sties; invading high quality natural communities including prairies, savannas, seeps and sedge meadows
Teasel grows in open sunny habitats, ranging from wet to dry conditions, while wet conditions are optimal


Sources of information:

DiTomaso, J.M. and E. Healy. Weeds of California and Other Western States, as yet published; Cheesman, O.D., 1998. The impact of some field boundary management practices development of Dipsacus fullonum L. flowering stems, and implications for conservation. Agriculture, Ecosystems and Environment 68 (1998) 41-49; Rayner, J.N. (ed.), 1961. Surfaced temperature frequencies for North America and Greenland. Arctic Meteorol. Res. Group Publ. 33,, Montreal, Que.


Question 3.2 Distribution/Peak frequency? C Reviewed Scientific Publication
Describe distribution:

Fairly widestread distribution, some parameters listed below for establishment A typical teasel population might ocupy 2,000 m2 of a field or extend for several kilometers along a roadway
Currently invades: fallow fields, pastures, roadside, waste places, ditches, riparian sites and other disturbed sties; invading high quality natural communities including prairies, savannas, seeps and sedge meadows
Teasel grows in open sunny habitats, ranging from wet to dry conditions, while wet conditions are optimal


Sources of information:

Werner, P.A., 1975. The biology of Canadian weeds. Can. J. Plant Sci. 55:783-794; Cheesman, O.D., 1998. The impact of some field boundary management practices development of Dipsacus fullonum L. flowering stems, and implications for conservation. Agriculture, Ecosystems and Environment 68 (1998) 41-49; Rayner, J.N. (ed.), 1961. Surfaced temperature frequencies for North America and Greenland. Arctic Meteorol. Res. Group Publ. 33,, Montreal, Que.


Worksheet A - Innate reproductive potential

Reaches reproductive maturity in 2 years or less No
Dense infestations produce >1,000 viable seed per square meter Yes
Populations of this species produce seeds every year. No
Seed production sustained over 3 or more months within a population annually No
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 No
Total points: 5
Total unknowns: 0
Total score: B?

Related traits:

a few seeds are produced by selfing, while most seed produced through cross pollination; no vegetative reproduction; a rosette forms a flowering stalk only after attaining a critical size of approximately 30 cm in diameter, so doesn't necessarily reach reprod. maturity in 2 years or less

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 prairieD, < 5%
valley and foothill grasslandD, < 5%
Great Basin grasslandC, 5% - 20%
vernal pool
meadow and seepC, 5% - 20%
alkali playa
pebble plain
Bog and Marshbog and fenC, 5% - 20%
marsh and swampD, < 5%
Riparian and Bottomland habitatriparian forest
riparian woodland
riparian scrub (incl.desert washes)D, < 5%
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): A
Distribution (highest score): C

Infested Jepson Regions

Click here for a map of Jepson regions

  • Central West
  • Sonoran Desert
  • Modoc Plateau
  • Northwest
  • Sierra Nevada
  • Sierra Nevada East
  • Southwest