Plant Assessment Form

Bromus japonicus

Synonyms: Bromus abolini Drob., Bromus chiapporianus de Not. Ex Nyman, Bromus commutatus Schrad., Bromus cyri Trin., Bromus gedrosianus Penzes, Bromus japonicus ssp. anatolicus (Boiss. & Heldr.) Penzes, Bromus japonicus Thunb. ex Murr. var. porectus Hack., Bromus japonicus var. susquarrosus (Borb.) Savul. & Rays, Bromus multiflorus DC. ex Lam. & DC, Bromus patulus Mert. & Koch, Bromus pendulus Schur. Bromus unilateralis Schur., Bromus vestitus Schrad.

Common Names: Japanese brome; Japanese chess

Evaluated on: 1/3/07

List committee review date: 14/02/2007

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

List commitee members

Joe DiTomaso
Peter Warner
Joanna Clines

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 B Reviewed Scientific Publication
Impact?
Four-part score BBDU Total Score
B
1.2 ?Impact on plant community B. Moderate Reviewed Scientific Publication
1.3 ?Impact on higher trophic levels D. Negligible Other Published Material
1.4 ?Impact on genetic integrity U. Unknown
2.1 ?Role of anthropogenic and natural disturbance in establishment B. Moderate Reviewed Scientific Publication
Invasiveness?
Total Points
8 Total Score C
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)
C. Low Observational
2.5 ?Potential for human-caused dispersal B. Moderate Observational
2.6 ? Potential for natural long-distance dispersal D. None Other Published Material
2.7 ?Other regions invaded C. Already invaded Observational
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? B Reviewed Scientific Publication
Identify ecosystem processes impacted:

Can be a litter accumulator, but not nearly to the level of medusahead. They are also capable of changing the fire frequency in an area, much like other introduced annual grasses.


Sources of information:

Ogle, S.M., D. Ojima, and W.A. Reiners. 2005. Biological Invasions 6(3):365-377


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

Competes for moisture with and displaces perennial grasses.


Sources of information:

DiTomaso, J. M., and E. A. Healy. 2007. Weeds of California and Other Western States. University of California Agriculture and Natural Resources Publication 3488. Oakland, CA. text here


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

Good forage for livestock and wildlife. No known negative impacts. Introduced as a livestock forage.


Sources of information:

DiTomaso, J. M., and E. A. Healy. 2007. Weeds of California and Other Western States. University of California Agriculture and Natural Resources Publication 3488. Oakland, CA. text here


Question 1.4 Impact on genetic integrity? U

There are nine native species of Bromus in California. No information on hybridization.


Sources of information:

Hickman, J. C. (ed.) 1993. The Jepson Manual, Higher Plants of California. University of California Press. Berkeley, CA


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

Mostly in disturbed sites but can invade undisturbed areas. Mechanical disturbance of the soil can greatly increase Japanese brome.


Sources of information:

DiTomaso, J. M., and E. A. Healy. 2007. Weeds of California and Other Western States. University of California Agriculture and Natural Resources Publication 3488. Oakland, CA. text here


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

Appears to be static in its movement


Sources of information:

DiTomaso, observational


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

Has steadily increased in the northern Great Plains region over the past 30 years, but appears to be static in its movement


Sources of information:

DiTomaso, observational


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

Cool season annual. Reproduces by seed.
Burning can reduce Japanese brome for 1-2 years but sites repopulated from the seedbank.


Sources of information:

DiTomaso, J. M., and E. A. Healy. 2007. Weeds of California and Other Western States. University of California Agriculture and Natural Resources Publication 3488. Oakland, CA. text here


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

Seeds can be dispersed by vehicles, soil movement, or as seed contaminants, but this is probable not common. Movement in hay is likely more common.


Sources of information:

DiTomaso, J. M., and E. A. Healy. 2007. Weeds of California and Other Western States. University of California Agriculture and Natural Resources Publication 3488. Oakland, CA. text here


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

Most seeds fall near parent plant but can disperse with water, mud, soil movement, or animals.


Sources of information:

DiTomaso, J. M., and E. A. Healy. 2007. Weeds of California and Other Western States. University of California Agriculture and Natural Resources Publication 3488. Oakland, CA. text here


Question 2.7 Other regions invaded? C Observational
Identify other regions:

Likely found in similar environments in other areas. Primarily a grassland species.


Sources of information:

DiTomaso, observational and other internet sources


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

Grassland, sagebrush communities, rangeland, fields, open disturbed sites, roadsides, crops. Thrives on fertile soils. Desert shrub-grassland communities, pinyon-juniper communities, and open areas in low elevation coniferous forests. Throughout California, mostly to 1000m. Common in northern region of the state.


Sources of information:

DiTomaso, J. M., and E. A. Healy. 2007. Weeds of California and Other Western States. University of California Agriculture and Natural Resources Publication 3488. Oakland, CA. text here


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

Most common in Great Basin grasslands.


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 No
Fragments easily and fragments can become established elsewhere No
Resprouts readily when cut, grazed, or burned No
Total points: 2
Total unknowns: 1
Total score: C?

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 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 grasslandD, < 5%
Great Basin grasslandC, 5% - 20%
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 woodland
piñon and juniper woodlandD, < 5%
Sonoran thorn woodland
Forestbroadleaved upland forest
North Coast coniferous forest
closed cone coniferous forest
lower montane coniferous forestD, < 5%
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

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