Plant Assessment Form

Rumex acetosella

Synonyms: Acetosella vulgaris

Common Names: sheep sorrel

Evaluated on: 21/8/03

List committee review date: 27/08/2004

Re-evaluation date:

Evaluator(s)

Jake Sigg
California Native Plant Society
338 Ortega St San Francisco CA 94122
415/731-3028
jakesigg@earthlink.net

List commitee members

Peter Warner
Joe DiTomaso
John Randall
Jake Sigg
Alison Stanton
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? 2.5 out of 5
Score Documentation
1.1 ?Impact on abiotic ecosystem processes U Reviewed Scientific Publication
Impact?
Four-part score UBBC Total Score
B
1.2 ?Impact on plant community B. Moderate Other Published Material
1.3 ?Impact on higher trophic levels B. Moderate Other Published Material
1.4 ?Impact on genetic integrity C. Minor/Low Other Published Material
2.1 ?Role of anthropogenic and natural disturbance in establishment B. Moderate Other Published Material
Invasiveness?
Total Points
12 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 Observational
2.5 ?Potential for human-caused dispersal B. Moderate Observational
2.6 ? Potential for natural long-distance dispersal C. Rare Observational
2.7 ?Other regions invaded C. Already invaded Other Published Material
3.1 ?Ecological amplitude/Range
(see Worksheet C)
A. Widespread Other Published Material
Distribution?
Total Score A
3.2 ?Distribution/Peak frequency
(see Worksheet C)
A. High 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:

Sources of information:

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

Displaces native grasses and forbs by root competition, shading. Can form large dense stands.
May reduce or eliminate mycorrhizae.


Sources of information:

Observational, Jake Sigg. Observational, Peter Warner.
Wilken D., Hannah L. Rumex acetosella L..(Polygonaceae) Sheep Sorreal, Red Sorreal. SBBG. 1998.


Question 1.3 Impact on higher trophic levels? B Other Published Material
Identify type of impact or alteration:

Reduces or eliminates faunal sustenance. On San Bruno Mtn, competes directly w/host plants for federally-listed Endangered butterflies: callippe silverspot, mission blue, and San Bruno Elfin.
Because its oxalates are documented as toxic to domestic livestock, it is possible that it could be toxic to wild mammals.
May reduce or eliminate mycorrhizae. By displacing native plants, I infer that fauna are deprived of sustenance. Sources state the plant is non-mycorrhizal; when it eliminates other plants, mycorrhizae would die.


Sources of information:

Observational, Jake Sigg.
For toxicity information: Kingsbury, J.M. Poisonous Plants of the United States and Canada. Prentice-Hall Inc. Englewood Cliffs, New Jersey. 1964. Pg. 231.
DiTomaso J. D., Healy E. H. Weeds of California and Other Western States. As yet unplished. 611-612
Wilken D., Hannah L. Rumex acetosella L..(Polygonaceae) Sheep Sorreal, Red Sorreal. SBBG. 1998


Question 1.4 Impact on genetic integrity? C Other Published Material

None known No hybrids with natives Rumex species observed or reported, but native spp exist.


Sources of information:

Observational, Jake Sigg.
Hickman, JC. 1993. The Jepson Manual: Higher Plants of California. UC Press.


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

Thrives on soil disturbance. Easily distributed by seed or nursery stock or other human transport agent. Seeds disperse w/wind, water, mud, animals, vehicles tires, ag and landscape operations, and as seed, grain, and hay contaminants.


Sources of information:

DiTomaso J. D., Healy E. H. Weeds of California and Other Western States. As yet unplished. 611-612


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

Slow but steady, mostly vegetatively.


Sources of information:

Observational, Jake Sigg.


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

Not extending range throughout state. Because base population and seed source is greater every year, there are more plants to produce propagules. Not extending range throughout the state.


Sources of information:

Observational, Jake Sigg, P.Warner, J. DiTomaso. Recorded 2004.


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

Primary spread by creeping rhizomes, which form large colonies; colonies flower abundantly. Spread by seedling regeneration is a lesser, but significant, factor.


Sources of information:

Observational, Jake Sigg, John Randall, Peter Warner, Joe DiTomaso. Recorded 2004.


Question 2.5 Potential for human-caused dispersal? B Observational
Identify dispersal mechanisms:

Too small for hay. Seeds don't adhere to clothing. Easily distributed by seed or nursery stock or other human transport agent. Seeds disperse w/wind, water, mud, animals, vehicles tires, ag and landscape operations, and as seed, grain, and hay contaminants.


Sources of information:

Observational, P.Warner.


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

Probably uncommon. Because it is common and widespread, it is not easy to determine the source of new plants. Seed is sufficiently heavy to make long-distance wind dispersal infeasible, and transport by birds is probably minimal.


Sources of information:

Observational, Jake Sigg, Joe DiTomaso. Recorded 2004.


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

An almost cosmopolitan plant.


Sources of information:

DiTomaso J. D., Healy E. H. Weeds of California and Other Western States. As yet unplished. 611-612
Kingsbury, J.M. Poisonous Plants of the United States and Canada. Prentice-Hall Inc. Englewood Cliffs, New Jersey. 1964. Pg. 231.
Wilken D., Hannah L. Rumex acetosella L..(Polygonaceae) Sheep Sorreal, Red Sorreal. SBBG. 1998.


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

Found in coastal dunes, common in coastal bluff scrub, coastal scrub, coastal prairie, closed cone coniferous forest. May be in lower montane coniferous forest. Unknown when introduced, but entered California previous to 1880. Found in 6 major ecotypes in CA.


Sources of information:

Wilken D., Hannah L. Rumex acetosella L..(Polygonaceae) Sheep Sorreal, Red Sorreal. SBBG. 1998.
Observational, Jake Sigg.


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

Found in more than 50% of coastal prarie.


Sources of information:

Observational, Jake Sigg, John Randall, Peter Warner, Joe DiTomaso.


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 No
Has quickly spreading vegetative structures (rhizomes, roots, etc.) that may root at nodes Yes
Fragments easily and fragments can become established elsewhere No
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, reservoirs
Aquatic Systemsrivers, streams, canals
estuaries
DunescoastalD, < 5%
desert
interior
Scrub and Chaparralcoastal bluff scrubB, 20% - 50%
coastal scrubB, 20% - 50%
Sonoran desert scrub
Mojavean desert scrub (incl. Joshua tree woodland)
Great Basin scrub
chenopod scrub
montane dwarf scrub
Upper Sonoran subshrub scrub
chaparralA, > 50%
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 fenD, < 5%
marsh and swamp
Riparian and Bottomland habitatriparian forestD, < 5%
riparian woodland
riparian scrub (incl.desert washes)C, 5% - 20%
Woodlandcismontane woodland
piñon and juniper woodland
Sonoran thorn woodlandD, < 5%
Forestbroadleaved upland forestD, < 5%
North Coast coniferous forestC, 5% - 20%
closed cone coniferous forestD, < 5%
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): A

Infested Jepson Regions

Click here for a map of Jepson regions

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