Pacific Island Ecosystems at Risk (PIER)


Acacia farnesiana


RISK ASSESSMENT RESULTS: High risk, score: 14


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.

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

Acacia farnesiana (syn. Acacia smallii Isely, Mimosa farnesiana L.), fragrant acacia, sweet acacia, Huisache, mimosa bush

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

y

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

y

3.03

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

n=0

y

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

4.01

Produces spines, thorns or burrs

y=1, n=0

y

4.02

Allelopathic

y=1, n=0

4.03

Parasitic

y=1, n=0

n

4.04

Unpalatable to grazing animals

y=1, n=-1

n

4.05

Toxic to animals

y=1, n=0

n

4.06

Host for recognized pests and pathogens

y=1, n=0

y

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

y

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

y

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

3

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

n

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

7.05

Propagules water dispersed

y=1, n=-1

n

7.06

Propagules bird dispersed

y=1, n=-1

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

y

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

n

8.02

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

y=1, n=-1

y

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

y

8.05

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

y=-1, n=1

Total score:

14

Supporting data:

Notes

Source

1.01

No evidence

1.02

It is the most widely distributed species of the genus, becoming naturalized in many regions of the tropics and subtropics from its origins in Central America. ...A major disadvantage is that A. farnesiana is an aggressive colonizer and is regarded as a weed in some areas where it has become naturalized (e.g. Australia and USA).

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.

1.03

No evidence

2.01

It is the most widely distributed species of the genus, becoming naturalized in many regions of the tropics and subtropics from its origins in Central America.

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.

2.02

2.03

(1)Approximate limits north to south: 33°N to 33°S

(2)Hardiness range 9A - 11 (3)Found at elevations between sea level and 1300 m

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.hortpix.com/pc46.htm (3)http://ecocrop.fao.org/

2.04

It is the most widely distributed species of the genus, becoming naturalized in many regions of the tropics and subtropics from its origins in Central America.

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.

2.05

Introduced widely in several countries

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.

3.01

It is the most widely distributed species of the genus, becoming naturalized in many regions of the tropics and subtropics from its origins in Central America. It is the most widely distributed species of the genus, becoming naturalized in many regions of the tropics and subtropics from its origins in Central America. ...A major disadvantage is that A. farnesiana is an aggressive colonizer and is regarded as a weed in some areas where it has become naturalized (e.g. Australia and USA).

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.

3.02

(1)Dry, open disturbed areas (2)There are some dense infestations at Lualualei, O'ahu, and Lihau, Maui; some overgrazed areas on Lana'i; and the Ha'upu area of Kaua'i, particularly Mahalapu.This thorny, deciduous shrub grows to 4 m in height, sometimes forming impenetrable thickets, although in most areas it forms a more open cover. (3)now naturalized and common, sometimes becoming a pest, in dry, open, disturbed areas, 2-400 m [disturbance weed - colonizes pasturelands and open, disturbed habitats, rivier banks; see below]

(1)Wagner et al. 1990. Manual of the flowering plants of Hawaii. Universiity of Hawaii Press, Honolulu. (2)http://www.botany.hawaii.edu/faculty/cw_smith/aca_far.htm (3)Wagner et al. 1990. Manual of the flowering plants of Hawaii. Universiity of Hawaii Press, Honolulu.

3.03

(1)A major disadvantage is that A. farnesiana is an aggressive colonizer and is regarded as a weed in some areas where it has become naturalized (e.g. Australia and USA). (2)An invasive species in Fiji, French Polynesia, New Caledonia, Solomon Islands, and Vanuatu (3)Acacia farnesiana is a principal weed in Australia, Fiji, Indonesia, Paraguay and Mexico. (4)A pasture weed in Australia (5)often forms thorny thickets, it can be a considerable nuisance during mustering and can also hinder stock access to water.

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.hear.org/pier/acfar.htm (3)Holm et al. 1997 An electronic atlas of weeds and invasive species. CD-ROM database Version 1. (4)http://www.northwestweeds.nsw.gov.au/mimosa_bush.htm (4)http://www.nrm.qld.gov.au/factsheets/pdf/pest/PP35.pdf

3.04

Disturbance weed and AG weed - see above

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.hear.org/pier/acfar.htm (3)Holm et al. 1997 An electronic atlas of weeds and invasive species. CD-ROM database Version 1.

3.05

Acacia dealbata is a principal weed in Australia. A. hebecladoides is a principal weed in Tanzania.

Holm et al. 1997 An electronic atlas of weeds and invasive species. CD-ROM database Version 1.

4.01

A. farnesiana is a spinescent shrub, or rarely a small tree, 2-7 m tall

4.02

AB: "Atriplex canescens, Acacia farnesiana, P. juliflora, Rhus trilobatus and Chrysothamnus nauseosus inhibited growth either by killing the newly-germinated seeds or by reducing coleoptile growth by 30% compared with the control." [lab experiment not necessarily relevant to field]

Hampton, C. O.; Singh, S. P. (1979) The presence of growth and germination inhibitors in the seeds of certain desert plants. Kansas Academy of Science, Transactions, 1979, Vol. 82, No. 2, pp. 87

4.03

No evidence

4.04

(1)readily eaten by stock, (2)However the thorny spines inhibit browsing so that only the outside branches are used. Mechanical top removal increased the preference value of huisache eight fold by removing the thorny top, stimulating new growth, and increasing crude protein contents of available browse.'

(1)http://www.nrm.qld.gov.au/factsheets/pdf/pest/PP35.pdf (2)Rasmussan, G.A. et al. 1983. Huisache Growth Browse Quality and Use Following Browsing. Journal of Range Management. 36(3): 337 - 342.

4.05

Pods used as animal feed

http://ecocrop.fao.org/

4.06

(1)Pests recorded
Insect pests:
Oncideres pustulata
(2)Fungi reported on this plant include: Camptomeris albizziae, Clitocybe tabescens, Hypocrea borneensis, Lenzites palisoti, L. repanda, Phyllachora acaciae, Phymatotrichum omnivorum, Phymatotrichum omnivorum Ravenelia austris, R. hieronymi, R. siliquae, R. spegazziniana, Schizophyllum commune, Systingophora hieronymi, Tryblidiella rufula, and Uromycladium notabile. It may also be parasitized by the flowering plants Dendrophthoe falcata and Santalum album (3) Uromycladium notabile is a specialist attacks several Acacia sspecies, and was considered of economic importance.

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.hort.purdue.edu/newcrop/duke_energy/Acacia_farnesiana.html
(3) http://www.forestresearch.co.nz/PDF/Path15UromycladiumrustsofAcacia.pdf

4.07

No evidence

4.08

(1)This thorny, deciduous shrub grows to 4 m in height, sometimes forming impenetrable thickets (2)thrives in dry localities [likely fire hazard]

(1)http://www.hear.org/pier/acfar.htm (2)http://ecocrop.fao.org/

4.09

It cannot grow in the shade.

http://www.ibiblio.org/pfaf/cgi-bin/arr_html?Acacia+farnesiana

4.1

(1)tolerates a wide soil range,.. (2)Thrives in dry localities and on loamy or sandy soils where it may serve as a sand binder. Will grow on loose sandy soil of river beds, on pure sand in plains of Punjab.

(1)http://nasa.utep.edu/chih/gardens/plants/acaciafarn.htm (2)http://www.hort.purdue.edu/newcrop/duke_energy/Acacia_farnesiana.html

4.11

Probably not - not a vine.

http://florawww.eeb.uconn.edu/acc_num/198500174.html

4.12

(1)'This thorny, deciduous shrub grows to 4 m in height, sometimes forming impenetrable thickets, although in most areas it forms a more open cover.' (2)forming thickets along watercourses.

(1)http://www.hear.org/pier/acfar.htm (2)http://www.nrm.qld.gov.au/factsheets/pdf/pest/PP35.pdf

5.01

Fabaceae

5.02

Fabaceae

5.03

Ability to fix nitrogen

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.

5.04

No evidence

6.01

Trees begin to flower from the third year, mainly from November to March.

http://www.hort.purdue.edu/newcrop/duke_energy/Acacia_farnesiana.html

6.02

'As soon as the seedlings are large enough to handle, prick them out into individual pots ..'

http://www.ibiblio.org/pfaf/cgi-bin/arr_html?Acacia+farnesiana

6.03

No evidence

6.04

No evidence

6.05

Probably not - the flower morphology (globose heads) does not suggest adaptation to specialist pollinators.

http://www.hear.org/pier/acfar.htm

6.06

Propagation by seed. [No evidence of spread in the wild by vegetative means.]

http://www.hear.org/pier/acfar.htm

6.07

Trees begin to flower from the third year, mainly from November to March.

http://www.hort.purdue.edu/newcrop/duke_energy/Acacia_farnesiana.html

7.01

Probably not - no evidence that the seeds have any means of attachment.

http://florawww.eeb.uconn.edu/acc_num/198500174.html

7.02

Valued as a forestry and ornamental tree. 'Descriptors: soil conservation; erosion control; shelterbelts; windbreaks; hedges; amenity; ornamental.'

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.

7.03

Probably not - seeds relatively large.

http://florawww.eeb.uconn.edu/acc_num/198500174.html

7.04

No evidence

7.05

No evidence

7.06

The persistent fruits have a glossy coat and contain seeds which are cherished by birds and other wildlife. [seeds are probably crushed for food]

http://edis.ifas.ufl.edu/ST005

7.07

No evidence that the seeds have any means of attachment.

7.08

Seeds are dispersed by ungulates which eat the pods.

http://www.hear.org/pier/acfar.htm

8.01

(1)seeds relatively large '...seeds chestnut-brown, in 2 rows, embedded in a dry spongy tissue, 7–8 mm long, ca 5.5 mm broad, smooth, elliptic, thick, only slightly compressed;' (2) 5-10 seeds per pod

(1)http://florawww.eeb.uconn.edu/acc_num/198500174.html (2)http://www.northwestweeds.nsw.gov.au/mimosa_bush.htm

8.02

Probably yes - 'Germination in Acacia farnesiana seeds was studied. The results indicated that seeds of this species are dormant due to impermeability of seed coat of water. The dormancy did not terminate during dry storage but different scarification treatments resulted in termination of dormancy. Mechanical and chemical scarifications proved most effective treatments while temperature treatments were not much effective.'

RANA-U {a}; NAUTIYAL-A-R. 1989. COAT IMPOSED DORMANCY IN ACACIA-FARNESIANA SEEDS. Seed-Research-New-Delhi. 17 (2): 122-127..

8.03

(1) 'Chemical: "Probably susceptible to: 1) translocated herbicides, including picloram, metsulfuorn-methyl, glyphosate and triclopyr, and possibly 2,4-D applied to the foliage, freshly cut stumps or by stem injection at standard rates; 2) residual herbicides, including tebuthiuron and hexazinone." (Swarbrick, 1997)'. (2) 'An experiment was carried out to study the efficacy of herbicide treatments in controlling two serious pasture weeds: Acacia farnesiana and Mimosa pteridofita [M. pteridifolia ?]. The following herbicides were applied to the stump after cutting: diesel oil, used engine lubricant oil, 2,4-D+picloram diluted in water or diesel oil, and a control (without herbicide). All herbicide treatments were tested on two sizes of the plants and two heights of cutting, except the lubricant oil. The shrub control and sprouting vigour were evaluated in all treatments. The results showed that cutting of plants is effective only when it is carried out at the soil surface level and followed by a specific her

(1)http://www.hear.org/pier/acfar.htm (2) Carmona, R.; Araujo Neto, B. S. C.; Pereira, R. C.2001. Control of Acacia farnesiana and of Mimosa pteridofita in pastures. Controle de Acacia farnesiana e de Mimosa pteridofita em pastagem. Pesquisa Agropecuária Brasileira. Vol.36, No.10, pp.1301-1307. (3)Ramírez Moreno, F.; Enríquez Carrillo, E.; Zarazúa, H. M.; Ortega García, C.; Silva Olivas, M. F. 1998. Huisache (Acacia farnesiana ) control with tebuthiuron on the Sonora central zone. Control de huizache (Acacia farnesiana ) con tebuthiuron en la parte central de Sonora. Técnica Pecuaria en México.Vol.36, No.3, pp.243-248.

8.04

(1)suited for coppicing; suited for pollarding (2)Although the aerial portions may be killed by fire, it soon regenerates from basal shoots.

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.botany.hawaii.edu/faculty/cw_smith/aca_far.htm

8.05

Don’t know


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