Pacific Island Ecosystems at Risk (PIER)


Verbesina encelioides


RISK ASSESSMENT RESULTS: High risk, score: 19


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment

Verbesina encelioides (Cav.) Benth. & Hook. F. ex A. Gray. Family - Asteraceae. Common Names(s) - American dogweed, butter daisy, crown-beard, golden crown-beard, South African daisy. Synonym(s) - Ximenesia encelioides.

Answer

Score

1.01

Is the species highly domesticated?

y=-3, n=0

n

0

1.02

Has the species become naturalized where grown?

y=1, n=-1

1.03

Does the species have weedy races?

y=-1, n=-1

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

y

1

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

1

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

2

3.02

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

n=0

y

2

3.03

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

n=0

y

4

3.04

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

n=0

3.05

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

n=0

y

2

4.01

Produces spines, thorns or burrs

y=1, n=0

n

0

4.02

Allelopathic

y=1, n=0

4.03

Parasitic

y=1, n=0

n

0

4.04

Unpalatable to grazing animals

y=1, n=-1

n

-1

4.05

Toxic to animals

y=1, n=0

y

1

4.06

Host for recognized pests and pathogens

y=1, n=0

n

0

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

n

0

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

n

0

4.09

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

y=1, n=0

n

0

4.10

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

y=1, n=0

y

1

4.11

Climbing or smothering growth habit

y=1, n=0

n

0

4.12

Forms dense thickets

y=1, n=0

n

0

5.01

Aquatic

y=5, n=0

n

0

5.02

Grass

y=1, n=0

n

0

5.03

Nitrogen fixing woody plant

y=1, n=0

n

0

5.04

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

y=1, n=0

n

0

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

0

6.02

Produces viable seed.

y=1, n=-1

y

1

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

y

1

6.05

Requires specialist pollinators

y=-1, n=0

n

0

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

n

-1

6.07

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

See left

1

1

7.01

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

y=1, n=-1

y

1

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

1

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

y

1

7.04

Propagules adapted to wind dispersal

y=1, n=-1

y

1

7.05

Propagules water dispersed

y=1, n=-1

n

-1

7.06

Propagules bird dispersed

y=1, n=-1

n

-1

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

y

1

7.08

Propagules survive passage through the gut

y=1, n=-1

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

y

1

8.02

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

y=1, n=-1

y

1

8.03

Well controlled by herbicides

y=-1, n=1

y

-1

8.04

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

y=1, n=-1

n

-1

8.05

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

y=-1, n=1

n

1

Total score:

19

Supporting data:

Notes

Source

1.01

No evidence.

 

1.02

1.03

2.01

(1) Native to United States: Kansas, Nebraska, Oklahoma, Colorado, Florida, New Mexico, Texas, Arizona, California; Mexico: Chihuahua, Coahuila, Durango, Nuevo Leon, San Luis Potosi, Sonora, Tamaulipas, Zacatecas, Aguascalientes.

(1) http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?41178 [cited 2009 Feb. 24].

2.02

(1) Native to United States: Kansas, Nebraska, Oklahoma, Colorado, Florida, New Mexico, Texas, Arizona, California; Mexico: Chihuahua, Coahuila, Durango, Nuevo Leon, San Luis Potosi, Sonora, Tamaulipas, Zacatecas, Aguascalientes.

(1) http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?41178 [cited 2009 Feb. 24].

2.03

(1) In native range found from elevations of 0 - 2,740 m.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

2.04

(1) Native to United States: Kansas, Nebraska, Oklahoma, Colorado, Florida, New Mexico, Texas, Arizona, California; Mexico: Chihuahua, Coahuila, Durango, Nuevo Leon, San Luis Potosi, Sonora, Tamaulipas, Zacatecas, Aguascalientes.

(1) http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?41178 [cited 2009 Feb. 24].

2.05

(1) V. encelioides has been introduced to the southwestern Arabian Peninsula, Argentina, the Pacific islands and Australia. (2) V. encelioides has successfully established on all continents except Antarctica.

(1) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 25]. (2) http://zu7lq2cc9q.scholar.serialssolutions.com/?sid=google&auinit=KR&aulast=Feenstra&atitle=
Biology+and+Impacts+of+Pacific+Island+Invasive+Species.+4.+Verbesina+encelioides,+
Golden+Crownbeard+(Magnoliopsida:+Asteraceae)&id=doi:10.2984/1534-6188(2008)62[161:BAIOPI]2.0.CO%3B2 [cited 2009 Feb. 25].

3.01

(1) Naturalized in Hawaii. (2) V. encelioides has naturalized in many warm regions of the world: southern United States, South America, the Bahamas, Cuba, Dominican Republic, Puerto Rico, Saudi Arabia, India, Ethiopia, Morocco, Botswana, Namibia, Israel and Australia.

(1) Wagner W.L., H. D. R., Sohmer S.H. (1999). Manual of the Flowering Plants of Hawaii. Honolulu Bishop Museum Press. (2) Feenstra, K. and D. Clements (2008). "Biology and Impacts of Pacific Island Invasive Species. 4. Verbesina encelioides, Golden Crownbeard (Magnoliopsida: Asteraceae)." Pacific Science [Internet]. 62(2): 161-176. [cited 2009 Feb. 25]. Available from: http://zu7lq2cc9q.scholar.serialssolutions.com/?sid=google&auinit=KR&aulast=Feenstra&atitle=
Biology+and+Impacts+of+Pacific+Island+Invasive+Species.+4.+Verbesina+encelioides,+
Golden+Crownbeard+(Magnoliopsida:+Asteraceae)&id=doi:10.2984/1534-6188(2008)62[161:BAIOPI]2.0.CO%3B2.

3.02

(1) V. encelioides is an abundant weed along roadsides and railway tracts and on the wastelands in North India. (2) In Australia Verbesina is found along roadsides, on stock routes and disturbed clay flats.

(1) Kaul, M. L. H. and P. D. Mangal (1987). "Phenology and Germination of Crownbeard (Verbesina encelioides)." Weed Science [Internet]. 35(4): 513-518. [cited 2009 Feb. 24]. Available from: http://www.jstor.org.eres.library.manoa.hawaii.edu/stable/pdfplus/4044521.pdf (2) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 25].

3.03

(1) V. encelioides is a postmonsoon and winter weed infesting maize, pearl millet, wheat, rice, peanut, gram, rape, and mustard fields in North India. (2) V. encelioides is a "common weed in maize and sorghum in Argentina and peanuts in the United States. It is recorded and completely overwhelming the crop in at least one locality in the south west of the Arabian Peninsula."

(1) Kaul, M. L. H. and P. D. Mangal (1987). "Phenology and Germination of Crownbeard (Verbesina encelioides)." Weed Science [Internet]. 35(4): 513-518. [cited 2009 Feb. 24]. Available from: http://www.jstor.org.eres.library.manoa.hawaii.edu/stable/pdfplus/4044521.pdf (2) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24].

3.04

(1) At Midway and Kure Atolls, V. encelioides significantly degrades the habitat for seabirds and native plants [but mostly a disturbance weed, see 3.02]

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

3.05

(1) Verbesina alternifolia is considered to be a weed and is naturalized in Japan.

(1) Holm, L. G., Pancho, J. V., Herberger, J. P. and Plucknett, D. L. (1979). A Geographical Atlas of World Weeds. John Wiley and Sons NewYork, USA

4.01

(1) No spines, thorns or burrs.

(1) Wagner W.L., H. D. R., Sohmer S.H. (1999). Manual of the Flowering Plants of Hawaii. Honolulu Bishop Museum Press.

4.02

(1) Allelopathic effects of Verbesina encelioides have also been noted and attribute to its dominant coverage and success in inhibiting native plant growth. This study used leaf, flower and stem extract and root leachate.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

4.03

(1) Not parasitic.

(1) http://www.omnisterra.com/bot/pp_home.cgi?name=verbesina&submit=Submit+Query&search=all [cited 2009 Feb. 24].

4.04

(1) Animals rarely graze on Verbesina unless other forage options are depleted or it is mixed in with other feed. (2) V. encelioides is extremely toxic, but is not readily eaten by stock except when animals are stressed and other feed is limited. (3) Resistant to deers.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24]. (2) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24]. (3) http://davesgarden.com/guides/pf/go/59964/ [cited 2009 Feb. 25].

4.05

(1) Toxic to sheep. (2) Toxicity has been reported from direct ingestion of V. encelioides. Animals rarely graze on Verbesina unless other forage options are depleted or it is mixed in with other feed.

(1) http://vm.cfsan.fda.gov/~djw/pltx.cgi?QUERY=verbesina+encelioides [cited 2009 Feb. 24]. (2) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

4.06

(1) No evidence

(1) Feenstra, K. and D. Clements (2008). "Biology and Impacts of Pacific Island Invasive Species. 4. Verbesina encelioides, Golden Crownbeard (Magnoliopsida: Asteraceae)." Pacific Science [Internet]. 62(2): 161-176. [cited 2009 Feb. 25]. Available from: http://zu7lq2cc9q.scholar.serialssolutions.com/?sid=google&auinit=KR&aulast=Feenstra&atitle=
Biology+and+Impacts+of+Pacific+Island+Invasive+Species.+4.+Verbesina+encelioides,+
Golden+Crownbeard+(Magnoliopsida:+Asteraceae)&id=doi:10.2984/1534-6188(2008)62[161:BAIOPI]2.0.CO%3B2.

4.07

(1) No human allergies or toxicity found in PubMed. (2) No evidence in Toxnet.

(1) http://www.ncbi.nlm.nih.gov/sites/entrez [cited 2009 Feb. 25]. (2) http://toxnet.nlm.nih.gov/cgi-bin/sis/search/r?./temp/~9YuZnS:@and+@kw+@term+Verbesina+encelioides [cited 2009 Feb. 25].

4.08

Unlikely (1) Annual species.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

4.09

(1) Full sun

(1) http://davesgarden.com/guides/pf/go/59964/ [cited 2009 Feb. 25].

4.10

(1) In nature, V. encelioides grows in a wide variety of soil types of diverse composition and texture. (2) Soil pH requirements: 7.9 to 8.5 (alkaline), 8.6 to 9.0 (strongly alkaline), over 9.1 (very alkaline).

(1) Kaul, M. L. H. and P. D. Mangal (1987). "Phenology and Germination of Crownbeard (Verbesina encelioides)." Weed Science [Internet]. 35(4): 513-518. [cited 2009 Feb. 24]. Available from: http://www.jstor.org.eres.library.manoa.hawaii.edu/stable/pdfplus/4044521.pdf (2) http://davesgarden.com/guides/pf/go/59964/ [cited 2009 Feb. 25].

4.11

(1) Annual- height: 0.3-1.66 meters

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

4.12

(1)Herbaceous annual- height: 0.3-1.66 meters

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

5.01

(1) Terrestrial

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

5.02

(1) Asteraceae.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

5.03

(1) Herbaceous Asteraceae

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

5.04

(1) An erect summer growing annual herb with a branching taproot with fibrous feeding roots.

(1) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 25].

6.01

No evidence.

 

6.02

(1) Propagates by seeds.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

6.03

Unknown

6.04

(1) V. encelioides has the ability for both self and cross fertilization.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

6.05

(1) Insect pollinated.

(1) Bryant, V. M. and G. D. Jones (2006). "Forensic palynology: Current status of a rarely used technique in the United States of America." Forensic Science International 163(3): 183-197.

6.06

(1) Propagates by seeds.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

6.07

(1) "Seeds germinate in autumn or early winter forming a rosette. Seedlings grow slowly during winter until flower stalks are produced in spring. Flowering commences in October or November and continues throughout summer while there is sufficient moisture. Plants die in Autumn. (2) In the Northwestern Hawaiian Islands, flowering is seen throughout the year, with the highest levels of

flowering observed from early April through November. (2) In a study by Kaul and Mangal 1987, flowering initiated 102-118 days after sowing and fruit set 10-12 days later.

(1) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 25] (2) (2) Feenstra, K. and D. Clements (2008). "Biology and Impacts of Pacific Island Invasive Species. 4. Verbesina encelioides, Golden Crownbeard (Magnoliopsida: Asteraceae)." Pacific Science [Internet]. 62(2): 161-176. [cited 2009 Feb. 25]. Available from: http://zu7lq2cc9q.scholar.serialssolutions.com/?sid=google&auinit=KR&aulast=Feenstra&atitle=
Biology+and+Impacts+of+Pacific+Island+Invasive+Species.+4.+Verbesina+encelioides,+
Golden+Crownbeard+(Magnoliopsida:+Asteraceae)&id=doi:10.2984/1534-6188(2008)62[161:BAIOPI]2.0.CO%3B2.

7.01

(1) Seeds can be dispersed long distances anchored by the seed bristle to clothing, bags, and other fibrous material. Seeds may be dispersed through road grading.

(1) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24].

7.02

(1) Not used widely as an ornamental. Plants of the Southwest website promotes the planting of V. encelioides for its fast growing abilities, bright colors and drought resistant qualities. The Arizona Department of Water Resources has the species listed on its 'Official Regulatory List of Low Water Use and Drought Tolerant Plants' as a landscape plant (Arizona Dept. of Water Resources website).

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

7.03

(1) Potential seed contaminant. (2) Seeds may be dispersed as a contaminant in pasture hay and cereal grain.

(1) http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?41178 [cited 2009 Feb. 24]. (2) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24].

7.04

(1) Seeds are dispersed by wind. (2) Seeds are equipped with bristles and wings and are wind dispersed for short distances.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24]. (2) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24].

7.05

(1) Seeds are dispersed by wind. (2) Seeds are equipped with bristles and wings and are wind dispersed for short distances. Seeds can be dispersed in the fur of animals, attached to clothing or by grading equipment.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24]. (2) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24].

7.06

(1) Seeds are dispersed by wind. (2) Seeds are equipped with bristles and wings and are wind dispersed for short distances. Seeds can be dispersed in the fur of animals, attached to clothing or by grading equipment.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24]. (2) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24].

7.07

(1) V. encelioides spreads only by seed, some are equipped with wings and fine bristles which makes them suited to dispersal by animals. Seeds anchored by the bristles in wool or fur may travel long distances.

(1) http://books.google.com/books?hl=en&lr=&id=sRCrNAQQrpwC&oi=fnd&pg=PA311&dq=verbesina+encelioides
+%2B+%22weed%22&ots=0P3OuMdcDl&sig=CyhzVqeMD7iCm25rTCwqURGVai0#PPA312,M1 [cited 2009 Feb. 24].

7.08

Unknown [possibly consumed indidentally by grazers]

 

8.01

(1) Seeds of Verbesina encelioides are numerous. In a small-scale study on Midway Atoll, a single flower head produced 300-350 seeds.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

8.02

(1) A study on Kure Atoll found that after 2 years of control most of the seed bank was eliminated and hand removal every 6 months was effective.

(1) Feenstra, K. and D. Clements (2008). "Biology and Impacts of Pacific Island Invasive Species. 4. Verbesina encelioides, Golden Crownbeard (Magnoliopsida: Asteraceae)." Pacific Science [Internet]. 62(2): 161-176. [cited 2009 Feb. 25]. Available from: http://zu7lq2cc9q.scholar.serialssolutions.com/?sid=google&auinit=KR&aulast=Feenstra&atitle=
Biology+and+Impacts+of+Pacific+Island+Invasive+Species.+4.+Verbesina+encelioides,+
Golden+Crownbeard+(Magnoliopsida:+Asteraceae)&id=doi:10.2984/1534-6188(2008)62[161:BAIOPI]2.0.CO%3B2.

8.03

(1) Study by Grichar and Sestak (1998) found the most effective control of V. encelioides ( 90% or better over 3 years) was accomplished with the post-emergence herbicieds (POST) of Bentazon, lactofen, pyridate, 2,4-Dichlorophenoxy butanoic acid (2, 4-DB), and 2, 4-DB with either pyridate or acifluorfen. In a later pre-emergence study and pre-plant incorporated herbicidal control, Grichar and Sestak 91999) found that Ethalfluralin followed by imazapic or lactofen provided 100% control. Ethalafluralin PPI combined with the pre-emergence oxyfluorfen provided control of 90% or better.

(1) http://www.hear.org/hnis/reports/verbesina_encelioides_hnis.pdf [cited 2009 Feb. 24].

8.04

(1) Controlled burns are an alternative to herbicide control.

(1) Feenstra, K. and D. Clements (2008). "Biology and Impacts of Pacific Island Invasive Species. 4. Verbesina encelioides, Golden Crownbeard (Magnoliopsida: Asteraceae)." Pacific Science [Internet]. 62(2): 161-176. [cited 2009 Feb. 25]. Available from: http://zu7lq2cc9q.scholar.serialssolutions.com/?sid=google&auinit=KR&aulast=Feenstra&atitle=
Biology+and+Impacts+of+Pacific+Island+Invasive+Species.+4.+Verbesina+encelioides,+
Golden+Crownbeard+(Magnoliopsida:+Asteraceae)&id=doi:10.2984/1534-6188(2008)62[161:BAIOPI]2.0.CO%3B2.

8.05

(1) No known biocontrol agents. There are at least 14 fungal pathogens that are associated with V. encelioides that could be tested for host specificity and efficacy.

(1) Feenstra, K. and D. Clements (2008). "Biology and Impacts of Pacific Island Invasive Species. 4. Verbesina encelioides, Golden Crownbeard (Magnoliopsida: Asteraceae)." Pacific Science [Internet]. 62(2): 161-176. [cited 2009 Feb. 25]. Available from: http://zu7lq2cc9q.scholar.serialssolutions.com/?sid=google&auinit=KR&aulast=Feenstra&atitle=
Biology+and+Impacts+of+Pacific+Island+Invasive+Species.+4.+Verbesina+encelioides,+
Golden+Crownbeard+(Magnoliopsida:+Asteraceae)&id=doi:10.2984/1534-6188(2008)62[161:BAIOPI]2.0.CO%3B2.


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