Plant Assessment Form

Digitalis purpurea

Common Names: foxglove

Evaluated on: 7/31/03

List committee review date: 01/08/2003

Re-evaluation date:

Evaluator(s)

Peter J. Warner
California Dept. of Parks and Recreation; CalEPPC
P. O. Box 603, Little River, CA 95456-0603
(707) 937-9176; (707) 937-2278
pwarner@mcn.org

List commitee members

Jake Sigg
Peter Warner
Joe DiTomaso
Doug Johnson
Brianna Richardson

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 U Reviewed Scientific Publication
Impact?
Four-part score UCCD Total Score
C
1.2 ?Impact on plant community C. Minor Observational
1.3 ?Impact on higher trophic levels C. Minor Observational
1.4 ?Impact on genetic integrity D. None Other Published Material
2.1 ?Role of anthropogenic and natural disturbance in establishment B. Moderate Observational
Invasiveness?
Total Points
14 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 C. Stable Observational
2.4 ?Innate reproductive potential
(see Worksheet A)
A. High
2.5 ?Potential for human-caused dispersal A. High Other Published Material
2.6 ? Potential for natural long-distance dispersal C. Rare Other Published Material
2.7 ?Other regions invaded B. Invades 1 or 2 ecological types 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)
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? U Reviewed Scientific Publication
Identify ecosystem processes impacted:

None known


Sources of information:

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

change in community composition; displacement of native species observed


Sources of information:

Peter Warner (personal observation); Joe DiTomaso (personal observation)


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

potential for wildlife poisoning (1) _ have generalist herbivores learned to avoid? Observations suggest plants are not browsed (2) inferred from toxicity of plant; reports on domestic animal injuries, deaths


Sources of information:

Question 1.4 Impact on genetic integrity? D Other Published Material

None known; probability remote due to lack of closely related native species inferred from lack of closely related species native to California


Sources of information:

Hickman, JC, et al. 1993. The Jepson Manual: Higher Vascular Plants of California


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

little, if any, disturbance necessary for establishment; grows in shaded to open, damp forests inferred from conditions where plants have become established (observations)


Sources of information:

Peter Warner (personal observation)


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

Does not appear to spread rapidly; plants do not generally establish in dense populations based on observations of infestations


Sources of information:

Peter Warner (personal observation)


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

probably slowly increasing, due to seed dispersal by birds; species has probably been widely dispersed for a long time (100+ years) observational; inference


Sources of information:

Peter Warner (personal observations)


Question 2.4 Innate reproductive potential? A
Describe key reproductive characteristics:

abundant production of small seeds (many per flower, many flowers/plant) written information; inference


Sources of information:

Hickman, JC, et al. 1993. The Jepson Manual: Higher Vascular Plants of California;
DiTomaso, J (unpublished data); Peter Warner (personal observation)


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

plants widely used horticulturally; seeds dispersed on clothing, footwear, etc. written information; deductive reasoning based on observations of infested areas


Sources of information:

DiTomaso, J (unpublished data);


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

wind, water, mud clinging to animal hooves & feet (1); often observed spreading along trails in damp areas (2) written information


Sources of information:

1. DiTomaso, J (unpublished data)
2. Warner, PJ. 2002-2005. Personal observations in Mendocino Co. 707/937-9176 corylus@earthlink.net


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

widespread in cool, moist areas of the North American west; northeast U. S. published information; observations


Sources of information:

Hickman, JC, et al. 1993. The Jepson Manual: Higher Vascular Plants of California;
DiTomaso, J (unpublished data); Peter Warner (personal observation)


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

common in cool, coastal forests, woodlands, scrub of Pacific Northwest; unknown types of habitats in Sierra Nevada, Cascades, Klamath Mtns.; probably introduced early in Euro-American settlement areas of the West observations; inference based on horticultural popularity, long-term medicinal use of plant


Sources of information:

Warner, PJ. 2002-2005. Personal observations, Mendocino Co. 707/937-1976 corylus@earthlink.net
2. Hickman, JC (editor). 1993. The Jepson Manual: Higher Plants of California. University of California Press, Berkeley
3. DiTomaso, J. 2005. unpublished data


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

common but sporadic in suitable habitat (1,2,3); not observed in a high proportion of vulnerable habitat types, but common within those invaded (1). extrapolation from local observations


Sources of information:

1. Warner, PJ. 2002-2005. Personal observations, Mendocino Co. 707/937-1976 corylus@earthlink.net
2. Hickman, JC (editor). 1993. The Jepson Manual: Higher Plants of California. University of California Press, Berkeley
3. DiTomaso, J. 2005. unpublished data


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 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: 7
Total unknowns: 0
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 prairie
valley and foothill grassland
Great Basin grassland
vernal poolD, < 5%
meadow and seep
alkali playa
pebble plainD, < 5%
Bog and Marshbog and fenD, < 5%
marsh and swampD, < 5%
Riparian and Bottomland habitatriparian forestD, < 5%
riparian woodland
riparian scrub (incl.desert washes)
Woodlandcismontane woodland
piñon and juniper woodland
Sonoran thorn woodland
Forestbroadleaved upland forestC, 5% - 20%
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

  • Cascade Range
  • Central West
  • Great Valley
  • Northwest
  • Sierra Nevada
  • Southwest