Research directed by C. Daehler (UH Botany) with funding from the Kaulunani Urban Forestry Program and US Forest Service

Information on Risk Assessments
Original risk assessment

Erigeron karvinskianus (Latin American fleabane, mexican daisy)

Answer

1.01

Is the species highly domesticated?

y=-3, n=0

n

1.02

Has the species become naturalized where grown?

y=-1, n=-1

y

1.03

Does the species have weedy races?

y=-1, n=-1

n

2.01

Species suited to tropical or subtropical climate(s) (0-low; 1-intermediate; 2-high) – If island is primarily wet habitat, then substitute “wet tropical” for “tropical or subtropical”

See Append 2

2

2.02

Quality of climate match data (0-low; 1-intermediate; 2-high) see appendix 2

2

2.03

Broad climate suitability (environmental versatility)

y=1, n=0

n

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

2.05

Does the species have a history of repeated introductions outside its natural range? y=-2

?=-1, n=0

y

3.01

Naturalized beyond native range y = 1*multiplier (see Append 2), n= question 2.05

y

3.02

Garden/amenity/disturbance weed y = 1*multiplier (see Append 2)

n=0

n

3.03

Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2)

n=0

n

3.04

Environmental weed y = 2*multiplier (see Append 2)

n=0

y

3.05

Congeneric weed y = 1*multiplier (see Append 2)

n=0

y

4.01

Produces spines, thorns or burrs

y=1, n=0

n

4.02

Allelopathic

y=1, n=0

n

4.03

Parasitic

y=1, n=0

n

4.04

Unpalatable to grazing animals

y=1, n=-1

4.05

Toxic to animals

y=1, n=0

n

4.06

Host for recognized pests and pathogens

y=1, n=0

n

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

n

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

4.09

Is a shade tolerant plant at some stage of its life cycle

y=1, n=0

n

4.1

Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island)

y=1, n=0

y

4.11

Climbing or smothering growth habit

y=1, n=0

n

4.12

Forms dense thickets

y=1, n=0

y

5.01

Aquatic

y=5, n=0

n

5.02

Grass

y=1, n=0

n

5.03

Nitrogen fixing woody plant

y=1, n=0

n

5.04

Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers)

y=1, n=0

n

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

6.02

Produces viable seed.

y=1, n=-1

y

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

6.05

Requires specialist pollinators

y=-1, n=0

n

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

n

6.07

Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1

See left

1

7.01

Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas)

y=1, n=-1

n

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

y

7.04

Propagules adapted to wind dispersal

y=1, n=-1

y

7.05

Propagules water dispersed

y=1, n=-1

n

7.06

Propagules bird dispersed

y=1, n=-1

n

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

n

7.08

Propagules survive passage through the gut

y=1, n=-1

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

y

8.02

Evidence that a persistent propagule bank is formed (>1 yr)

y=1, n=-1

8.03

Well controlled by herbicides

y=-1, n=1

y

8.04

Tolerates, or benefits from, mutilation, cultivation, or fire

y=1, n=-1

8.05

Effective natural enemies present locally (e.g. introduced biocontrol agents)

y=-1, n=1

Total score:

11

Source

Notes

1.01

No evidence.

1.02

(1)Naturalized in California, 2)New Zealand, 3)Hawaii.

http://www.calflora.org/cgi/calflora_query?one=T&special=photo&where-calrecnum=3145 2)http://envbop.govt.nz/www/green/weed78.htm (3)Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu.

1.03

No evidence.

2.01

(1)Native to the Neotropics from Mexico to Venezuela, Chile and the Antilles. (2)Native to tropical South America.

(1)Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu.(2)Plant master 5.5 CD_ROM database.

2.02

2.03

1)Sunset USDA: 9b-10 2)USDA zones 7-10 3)It prefers the coastal climate and the interior heat of summer does make it shut down. But, as soon as the weather is a cool again in fall, it perks right up and blooms until hard frost.

1)http://www.desert-tropicals.com/Plants/Asteraceae/Erigeron_karvinskianus.html 2)http://www.we-du.com/wildflwr1.htm 3)http://www.mountainvalleygrowers.com/erykarvinskianus.htm

2.04

(1)Naturalized in California, 2)New Zealand, 3)Hawaii.

http://www.calflora.org/cgi/calflora_query?one=T&special=photo&where-calrecnum=3145 2)http://envbop.govt.nz/www/green/weed78.htm (3)Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu.

2.05

see above

3.01

(1)Naturalized in California, 2)New Zealand, 3)Hawaii.

http://www.calflora.org/cgi/calflora_query?one=T&special=photo&where-calrecnum=3145 2)http://envbop.govt.nz/www/green/weed78.htm (3)Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu.

3.02

No evidence.

3.03

No evidence.

3.04

(1)A major problem on Kauai, Hawai‘i; spreading elsewhere. A serious weed on La Réunion.
(2) forms dense stands on North island of New Zealand, Under the Biosecurity Act 1993, it is illegal to sell, propagate or distribute Mexican daisy. (3)Bushland Weed of the Sydney Region (4)Dubautia latifolia --The threats to this species include competition from the alien plants Passiflora mollissima, Rubus argutus, Lonicera japonica (Japanese honeysuckle), Acacia mearnsii (black wattle), Hedychium sp. (ginger), Erigeron karvinskianus (daisy fleabane), and Psidium cattleianum; (5)Destruction of habitat by feral goats and pigs and competition with Erigeron karvinskianus (daisy fleabane) are major threats to Exocarpos luteolus (6)Cyanea dunbarii -- The major threats to this single population of Cyanea dunbarii on Molokai are competition with the non-native plants Buddleia asiatica (butterfly bush), Erigeron karvinskianus (daisy fleabane)

(1)http://www.hear.org/pier3/erkar.htm (2)http://www.doc.govt.nz/Conservation/003~Weeds/Mexican-Daisy.asp (3)http://www.zip.com.au/%7Eaabr/info/weed_lists/weed01.html (4)http://www.eswr.com/f1170.txt [Federal Register: November 7, 2000 (Volume 65, Number 216) Page 66807-66885] (5)http://endangered.fws.gov/r/fr94530.html (6)http://policy.fws.gov/library/00fr83157.html

3.05

(1)E. annus, E. canadensis and E. philadelphicus are listed as weeds of cultivated fields, waste places, roadsides and pastures. (2) E. canadensis is a weed throughout the Hawaiian islands.

(1)Lorenzi, H. and Jeffery, L. S. 1987. Weeds of the United States and their control. Van Nostrand Reinhold Company, New York. (2) Pope, W. 1929. Manual of Wayside plants of Hawaii. Advertiser publishing Company, Ltd. Honolulu.

4.01

No evidence.

Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu.

4.02

No evidence.

4.03

No evidence.

4.04

No information.

4.05

No evidence.

4.06

No information.

4.07

No evidence.

4.08

No information regarding fire ecology.

4.09

(1)Requires full sun. (2)Requires to full to half sun.

(1)http://plantsdatabase.com/go/1648.html (2)Plant master 5.5 CD-ROM database.

4.1

(1)Soil type: loam, pH neutral. (2)Soil range: mostly sandy to some clay and pH range 5.5 to 7.5 (3)tolerates a wide range of soil

(1)Plant master 5.5 CD_ROM database. (2)http://www.neoflora.com/cgi-bin/plant_profile.cgi?plant_sid=10076 (3)http://www.pnc.com.au/~wbrouwer/framesetpr1.htm

4.11

No evidence. It is not a vine.

4.12

form dense mats of ground cover, 1 ft tall

http://www.doc.govt.nz/Conservation/003~Weeds/Mexican-Daisy.asp

5.01

5.02

5.03

5.04

(1) Perennial sprawling herb. (2)'Plants of E. karvinskianus however characteristically produce a woody or lignescent caudex, ligniescent lower stem, and range upto 1 m in height.'

(1)Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu.(2)Nesom, G. L. 1998. Two new species of Erigeron (Asteraceae: Astereae) from Mexico. Phytologia. 85(4): 288-290

6.01

No evidence.

6.02

a prolific seeder

http://www.doc.govt.nz/Conservation/003~Weeds/Mexican-Daisy.asp

6.03

No information.

6.04

No information.

6.05

Probably not - flower is typical of Asteraceae and does not reveal any adaptation to a specialist pollinator.

6.06

Propagation by seed. (20 'E. karvinskianus may root adventitiously at nodes when the stems are decumbent or prostrate but this apparently is uncommon to rare and observation of hundreds of plants collected over the entire range of this species show none with the characteristic colonial habit of E. fluens.'

http://www.hear.org/pier3/erkar.htm (2)Nesom, G. L. 1998. Two new species of Erigeron (Asteraceae: Astereae) from Mexico. Phytologia. 85(4): 288-290

6.07

Probably 1year - it’s a herb -sometimes with woody stems. No direct evidence.

7.01

Propagules do not have any means of attachment.

Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu.

7.02

1)The species have showy flowers. 2) It is a common garden plant. Due its ornamental value it is likely to be introduced intentionally.

1)Plant master 5.5 CD-ROM database. 2)http://www.hear.org/pier3/erkar.htm

7.03

sometimes spread through contaminated topsoil and potting mix.

http://www.doc.govt.nz/Conservation/003~Weeds/Mexican-Daisy.asp

7.04

Wind dispersed seed

http://envbop.govt.nz/www/green/weed78.htm

7.05

7.06

7.07

Propagules have no means of attachment.

7.08

No information.

8.01

1)Achenes pale brown, ca. 1 mm long 2)a prolific seeder (eaisly 100+ flowerheads per m2)

Wagner,W. L., D. R. Herbst & S. H. Sohmer. 1990. Manual of flowering plants of Hawaii.University of Hawaii at Press. Honolulu. 2)http://www.doc.govt.nz/Conservation/003~Weeds/Mexican-Daisy.asp

8.02

No information.

8.03

Chemical Control
Versatill mixed at 10 ml in 10 litres of water.
Roundup mixed at 100 ml in 10 litres of water

http://envbop.govt.nz/www/green/weed78.htm

8.04

No information.

8.05

Don’t know.