Plant Assessment Form

Avena barbata

Common Names: slender oat

Evaluated on: 12/27/04

List committee review date: 11/02/2005

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

List commitee members

Carla Bossard
John Randall
Cynthia Roye
Jake Sigg
Peter Warner

General Comments

Many papers describe A. barbata and A. fatua together. There is much less specific information on A. barbata, so many of my answers assume that it is similar to A. fatua.

Table 2. Criteria, Section, and Overall Scores

Overall Score? Moderate
Alert Status? No Alert
Documentation? 3.5 out of 5
Score Documentation
1.1 ?Impact on abiotic ecosystem processes B Reviewed Scientific Publication
Impact?
Four-part score BACD Total Score
B
1.2 ?Impact on plant community A. Severe Reviewed Scientific Publication
1.3 ?Impact on higher trophic levels C. Minor Observational
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 C. Stable Observational
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 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 A
3.2 ?Distribution/Peak frequency
(see Worksheet C)
A. High

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:

Replacement of perennial grasslands with annuals like Avena increases fire frequencies.


Sources of information:

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

Outcompete other grasses (1). Allelopathic (2). Forms extensive, fibrous root system (3,4). "Wild oats are renowned for their competitive ability" (1).


Sources of information:

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

Has both positive and negative impacts.


Sources of information:

Weed committee personal observations.


Question 1.4 Impact on genetic integrity? D Reviewed Scientific Publication

none No native Avena species.


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?
C Observational
Describe role of disturbance:

Needs disturbance to establish. Often associated with agricultural fields.


Sources of information:

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

Well-established, so currently not spreading much.


Sources of information:

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

Well-established throughout California, so probably not spreading very much.


Sources of information:

1. DiTomaso and Healy. In prep.


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

Cool-season annual grass. In California, seeds germinate after first significant rain in the fall, until early spring. Flowers March-June. Wind-pollinated and self-compatible (1). Buried seeds often remain dormant until exposed by cultivation or other disturbance (1). In Malta, only a few viable but dormant seeds were present at the end of three years (2). Produce 1000 to 10,000 seeds/m2 (4). Requires cold for floral induction, more so than A. fatua (5).


Sources of information:

1. DiTomaso and Healy in prep
2. Holm et al. 1997
4. Medd 1996
5. Paterson, J. G., W. J. R. Boyd, and N. A. Goodchild. 1976. Vernalization and photoperiod requirement of naturalized Avena-Fatua and Avena-Barbata in western Australia. Journal of Applied Ecology 13(1): 265-272


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

Contaminent of grain, spread by agricultural machinery (1). Often contaminates seeds stocks in U.S. (2)


Sources of information:

1. Medd, R. W. 1996. Wild oats-what is the problem? Plant Protection Quarterly 11(SUPPL. 1): 183-184.
2. Holm et al. 1997


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

Possibly wind, but unlikely


Sources of information:

1. Medd, R. W. 1996. Wild oats-what is the problem? Plant Protection Quarterly 11(SUPPL. 1): 183-184.


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

OR, WA, NV, AZ, NM, MA (1). Argentina, Australia, Chile, France, Greece, Hawaii, India, Israel, Lebanon, Malta, Portugal, South Africa, Uruguay (2). In Australia, prefers cooler areas with more rainfall compared to A. fatua (3) .


Sources of information:

1. DiTomaso and Healy 1997
2. Holm et al. 1997
3. Paterson, J. G. 1976. The distribution of Avena-Spp naturalized in Western Australia. Journal of Applied Ecology 13(1): 257-264.


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

May have arrived with contaminated grain (1). Planted for forage and well-established by late 1700's (2).


Sources of information:

1. Sharma and Vanden born 1978
2. DiTomaso and Healy in prep.


Question 3.2 Distribution/Peak frequency? A
Describe distribution:

"Ubiquitous"


Sources of information:

DiTomaso and Healy in prep


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 Yes
Seeds remain viable in soil for three or more years No
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: 6
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
DunescoastalD, < 5%
desert
interior
Scrub and Chaparralcoastal bluff scrub
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
chaparralD, < 5%
Grasslands, Vernal Pools, Meadows, and other Herb Communitiescoastal prairieB, 20% - 50%
valley and foothill grasslandD, < 5%
Great Basin grasslandD, < 5%
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 woodlandD, < 5%
piñon and juniper woodland
Sonoran thorn woodland
Forestbroadleaved upland forest
North Coast coniferous forestD, < 5%
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): B

Infested Jepson Regions

Click here for a map of Jepson regions

  • Cascade Range
  • Central West
  • Desert Province
  • Mojave Desert
  • Sonoran Desert
  • Modoc Plateau
  • Sierra Nevada
  • Sierra Nevada East
  • Southwest