Plant Assessment Form

Kochia scoparia

Synonyms: Bassia scoparia, Bassia sieversiana, Chenopodium scoparia, Kochia alata, Kochia parodii, Kochia sieversiana, Kochia trichophila, Kochia virgata

Common Names: kochia; belvedere; belvedere-cypress; fireball; fireweed; Mexican burningbush; mock cypress

Evaluated on: 3/17/05

List committee review date: 08/07/2005

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

List commitee members

Jake Sigg
Peter Warner
Bob Case
John Knapp
Elizabeth Brusati

General Comments

No general comments for this species

Table 2. Criteria, Section, and Overall Scores

Overall Score? Limited
Alert Status? No Alert
Documentation? 3 out of 5
Score Documentation
1.1 ?Impact on abiotic ecosystem processes B Reviewed Scientific Publication
Impact?
Four-part score BBCD 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 Other Published Material
2.1 ?Role of anthropogenic and natural disturbance in establishment C. Minor Reviewed Scientific Publication
Invasiveness?
Total Points
10 Total Score C
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 Other Published Material
2.4 ?Innate reproductive potential
(see Worksheet A)
A. High Reviewed Scientific Publication
2.5 ?Potential for human-caused dispersal D. Does not occur Other Published Material
2.6 ? Potential for natural long-distance dispersal B. Occasional Other Published Material
2.7 ?Other regions invaded C. Already invaded Other Published Material
3.1 ?Ecological amplitude/Range
(see Worksheet C)
B. Moderate 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 create positive feedbacks between nutrient levels and plants. Much more common to other western states than to California. Densities there much higher as well. May not cause the same impact in California. Kochia invaded a site in Colorado that had N and water additions. Twenty years after additions had stopped, Kochia still dominated the community. N availability in soils under Kochia may be maintained by tissue chemistry favorable to microbial decomposition and release of nitrogen. Soils under Kochia had less plant-induced heterogeneity in nutrients, greater C and N mineralization, and higher levels of microbial biomass than soils associated with other species (1).


Sources of information:

1. Vinton, M. A. and I. C. Burke. 1995. Interactions between individual plant species and soil nutrient status in shortgrass steppe. Ecology 76(4): 1116-1133.


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

Highly competitive in nutrient-rich soils, possible allelopathic effects on other species. Can maintain dominance even after nutrient additions stop (1). Litter has allelopathic properties that affect crop plants and kochia seedlings (2). Was the pioneer species in a mine rehabilitation site but was quickly replaced by grasses. Kochia appears to have acted as a nurse crop. Although it is allelopathic, the compounds appear to create autotoxicity that hastens its own demise (3).


Sources of information:

1. Vinton and Burke 1995.
2. DiTomaso, J., and E. Healy. in prep. Weeds of California and Other Western States
3. Wali, M. K. 1999. Ecological succession and the rehabilitation of disturbed terrestrial ecosystems. Plant & Soil 213(1-2): 195-220.


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

Causes hepatotoxicity with photsensitization, renal disease, and polioencephalomalacia to livestock. However, still used as a forage crop (1). No information on effects on wildlife. Likely to have some impact if wildlife is forced to eat it.


Sources of information:

Burrows, G. E. 1993. Kochia scoparia: A noxius weed pest, livestock toxicant or remarkable livestock feed. Toxicon 31(2): 116.


Question 1.4 Impact on genetic integrity? D Other Published Material

Two native Kochia species, but no information on hybridization. Not expected to hybridize as the two native species are found in the desert.


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?
B Observational
Describe role of disturbance:

Inhabits disturbed areas (1). Pioneer species (2). In Colorado, was present in both logged forest and undisturbed, protected ponderosa-pine/Douglas fir forest (3). In California, however, kochia is not often found in wildland areas. It is primarily restricted to disturbed sites, roadsides and croplands.


Sources of information:

1. DiTomaso and Healy in prep.
2. Wali 1999
3. Fornwalt, P. J., M. R. Kaufmann, L. S. Huckaby, J. M. Stoker, and T. J. Stohlgren. 2003. Non-native plant invasions in managed and protected ponderosa pine/Douglas-fir forests of the Colorado Front Range. Forest Ecology & Management 177(1-3): 515-527.


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

Appears to move but not rapidly.


Sources of information:

DiTomaso, observational.


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

Expanding range in California (1).


Sources of information:

1. DiTomaso and Healy in prep.


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

Summer annual (1).Produces 12,000 seeds per plant (2). Seeds on soil surface survive 1-2 years (1) but buried seeds can remain viable for 36 months or more(1,3). Mowed or grazed plants resprout from base (1).


Sources of information:

1. DiTomaso, J., and E. Healy. in prep. Weeds of California and Other Western States.
2. Thompson, C. R., D. C. Thill, and B. Shafii. 1994. Germination characteristics of sulfonylurea-resistant and -susceptible kochia (Kochia scoparia). Weed Science 42: 50-56.
3. Zorner, P. S., R. L. Zimdahl, and E. E. Schweizer. 1984. Effect of depth and duration of seed burial on kochia (Kochia scoparia). Weed Science 32(5): 602-607.


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

Used to be planted for livestock forage and as an ornamental, but no longer (1). Recommended as an annual for cool, moist conditions, but not in California (2).


Sources of information:

1. DiTomaso and Healy in prep
2. University of Illinois Extension. Gardening with Annuals - Plants for Specific Uses. Accessed on-line 3/17/05, Available: http://www.urbanext.uiuc.edu/annuals/uses.html#8.


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

Senesced plants break off at the base and scatter fruits as they tumble in the wind (1, 2). 99.9% of shed pollen was estimated to be deposited within 154m of the source (3). Some seed may move long distances by this tumble action.


Sources of information:

1. DiTomaso and Healy in prep.
2. Boerboom, C. 1993. Kochia. Pacific Northwest Extension Publication. PNW460
3. Mulugeta D., B. D. Maxwell, P. K. Fay, and W. E. Dyer. 1994. Kochia (Kochia scoparia) Pollen Dispersion, Viability and Germination. Weed Science 42: 548-552.


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

Native to Asia. Present in most contiguous US states except possibly Maryland and a few southern states. Common in northern plains and listed as a noxious weed in Colorado, Minnesota, Washington, and Oregon (1). Introduced to the US as an ornamental in the early 1900's (2). Scoring as C because already widespread in California.


Sources of information:

1. DiTomaso and Healy in prep.
2. Khan, M. A., B. Gul, and D. J. Weber. 2001. Influence of salinity and temperature on the germination of Kochia scoparia. Wetlands Ecology and Management. 9:483-489.


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

Inhabits roadsides, fields, disturbed places, crop fields. Tolerates alkaline or saline soil and drought. Central Valley, San Francisco Bay region, Central Coast, South Coast, Mojave and Sonoran deserts, Great Basin, to 1500m (1). Can maintain high productivity at salinity up to 40% of seawater (2).


Sources of information:

1. DiTomaso and Healy in prep
2. Burrows 1993.


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

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 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 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: 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
Dunescoastal
desert
interior
Scrub and Chaparralcoastal bluff scrub
coastal scrubD, < 5%
Sonoran desert scrubC, 5% - 20%
Mojavean desert scrub (incl. Joshua tree woodland)
Great Basin scrubD, < 5%
chenopod scrubD, < 5%
montane dwarf scrub
Upper Sonoran subshrub scrubD, < 5%
chaparralD, < 5%
Grasslands, Vernal Pools, Meadows, and other Herb Communitiescoastal prairieD, < 5%
valley and foothill grasslandD, < 5%
Great Basin grasslandD, < 5%
vernal pool
meadow and seep
alkali playaD, < 5%
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 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): B
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
  • Great Basin Province
  • Modoc Plateau
  • Sierra Nevada East
  • Desert Province
  • Mojave Desert
  • Sonoran Desert