Plant Assessment Form

Stipa manicata

Synonyms: Nassella manicata (Desv.) Barkworth; Nassella formicarum auct. non (Delile) BarkworthStipa formicarum Delile

Common Names: Andean tussockgrass; tropical needlegrass

Evaluated on: 5/19/11

List committee review date:

Re-evaluation date:

Evaluator(s)

Elizabeth Brusati, Science Program Manager
Cal-IPC
1442-A Walnut St. #462, Berkeley, CA 94709
510-843-3902
edbrusati@cal-ipc.org
Joseph M. DiTomaso, Specialist in Cooperative Extension
Dept. of Plant Sciences, University of California-Davis
Mail Stop 4, One Shields Ave., Davis CA 95616
530-754-8715
jmditomaso@ucdavis.edu

No list committee members listed

General Comments

Name based on Jepson Manual, 2nd edition (2011). The first edition listed this species as Nassella manicata.

Table 2. Criteria, Section, and Overall Scores

Overall Score? Limited
Alert Status? No Alert
Documentation? 2 out of 5
Score Documentation
1.1 ?Impact on abiotic ecosystem processes C Observational
Impact?
Four-part score CCCU Total Score
C
1.2 ?Impact on plant community C. Minor Observational
1.3 ?Impact on higher trophic levels C. Minor Other Published Material
1.4 ?Impact on genetic integrity U. Unknown No Information
2.1 ?Role of anthropogenic and natural disturbance in establishment B. Moderate Observational
Invasiveness?
Total Points
10 Total Score C
2.2 ?Local rate of spread with no management B. Increases less rapidly Anecdotal
2.3 ?Recent trend in total area infested within state B. Increasing less rapidly Observational
2.4 ?Innate reproductive potential
(see Worksheet A)
B. Moderate Other Published Material
2.5 ?Potential for human-caused dispersal C. Low Observational
2.6 ? Potential for natural long-distance dispersal C. Rare Other Published Material
2.7 ?Other regions invaded D. Not known anywhere else Other Published Material
3.1 ?Ecological amplitude/Range
(see Worksheet C)
B. Moderate Observational
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? C Observational
Identify ecosystem processes impacted:

Could enhance fuel loads in coastal grasslands due to its bulk, but such systems are already very susceptible to fire through grass fuel accumualation.


Sources of information:

Information reported by Peter Warner, Mendocino County, 12/9/2010


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

Displaces native perennial grasses and forbs (many)


Sources of information:

Information reported by Peter Warner, Mendocino County, 12/9/2010


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

Other Nassella spp are considered unpalatable.


Sources of information:

McLaren 2004,


Question 1.4 Impact on genetic integrity? U No Information

Potentially could hybridize with native California Nassella/Stipa species. Did not find reports that this has been seen, however. There are several native Nassella spp. in California.


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?
B Anecdotal
Describe role of disturbance:

Occasionally invades areas with little or no natural disturbance, but is most often found on disturbed roadsides.


Sources of information:

Information reported by Peter Warner, Mendocino County, 12/9/2010


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

Reports of spread but not sure how much or how quickly.


Sources of information:

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

Has been seen spreading to new sites.


Sources of information:

Information reported by Peter Warner, Mendocino County, 12/9/2010


Question 2.4 Innate reproductive potential? B Other Published Material
Describe key reproductive characteristics:

Perennial grass. Can self-sow once established. Requires little to no water.


Sources of information:

Brenzel 2001


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

Ornamental grass. Could spread along roadsides.


Sources of information:

Information reported by Peter Warner, Mendocino County, 12/9/2010


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

Possibly birds. Sparrows at Jenner Headlands, Sonoma County, have been seen using it, but awns probably minimize its use as a food source. Animal dispersal can also occur when seeds cling to fur.


Sources of information:

Information reported by Peter Warner, Mendocino County, 12/9/2010


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

Nassella manicata is native to Ecuador, Chile, Argentina, and Uruguay, growing on the foothills of the Andes Mountains. It is established in three California counties, growing in disturbed sites, including grazed meadows and old gold tailings. It has also been recorded from Mississippi; it is not known whether the Mississippi population has persisted (Utah State, Grass Manual).


Sources of information:

Utah State University 2010


Section 3: Distribution
Question 3.1 Ecological amplitude/Range? B Observational

Coastal terrace prairie, coastal scrub; Sonoma County, Bodega Bay north to Salt Pt. State Park, within 5 miles of coast


Sources of information:

Information reported by Peter Warner, Mendocino County, 12/9/2010


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

Sources of information:

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 Unknown
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 Yes
Total points: 4
Total unknowns: 1
Total score: B?

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 scrubD, < 5%
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 prairieD, < 5%
valley and foothill grassland
Great Basin grassland
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 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): D

Infested Jepson Regions

Click here for a map of Jepson regions

  • Northwest