Pacific Island Ecosystems at Risk (PIER)


Parkinsonia aculeata


RISK ASSESSMENT RESULTS: High risk, score: 20


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

Parkinsonia aculeata (Jerusalum thorn, Mexican palo verde)

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

1

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

y

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

n

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

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

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

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

y

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

2

7.01

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

y=1, n=-1

y

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

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

7.05

Propagules water dispersed

y=1, n=-1

y

7.06

Propagules bird dispersed

y=1, n=-1

y

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

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:

20

Supporting data:

Source

Notes

1.01

No evidence

1.02

'The establishment of extensive naturalized weedy populations, especially in Australia, has stimulated research into the biological control of this species … ' 'Parkinsonia aculeata has a widespread distribution in Africa, and is becoming naturalized in many areas'.

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

1.03

No evidence

2.01

List of countries with natural populations: Central America, Costa Rica, Guatemala, Nicaragua, North America and Mexico.

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

2.02

'Although the majority of authors agree that P. aculeata is native to the New World, there are difficulties in identifying the historical distribution of the species. The literature suggests P. aculeata was well established throughout Mexico, the West Indies and South America by the 18th century, but that the natural or original distribution of P. aculeata in the Americas may have been more restricted than either that or present day distributions. Several authors have noted that the natural distribution of P. aculeata is difficult to ascertain (e.g. Isley, 1975; McVaugh, 1987; Woods, 1992). Extensive isolated pure stands of P. aculeata are found throughout southern USA, Mexico and Central America at seasonally flooded former lake bed sites, coastal estuaries or lagoons with deep black vertisols. P. aculeata is rarely found outside these sites, which are often highly disjunct, except as a putatively recent invader of roadsides, railway lines or irrigation channels, or where planted. Hughes (1989) has suggeste

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

2.03

(1)Approximate limits north to south: 38°N to 34°S Altitude range: 0 - 600 m (2)USDA hardiness zones: 8B through 11; Adapted to arid regions, one of the best choices for hot, dry locations and its salt-tolerance makes it ideal for seaside plantings. Jerusalem thorn has been used to revegetate desertified regions in Africa and Pakistan. Jerusalem thorn is highly adapted to life in the desert. (3) Dry Coastal and Dry Limestone Regions:

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://edis.ifas.ufl.edu/ST431 (3)http://cgsc.biology.yale.edu/precolog.html

2.04

'Although the majority of authors agree that P. aculeata is native to the New World, there are difficulties in identifying the historical distribution of the species. The literature suggests P. aculeata was well established throughout Mexico, the West Indies and South America by the 18th century, but that the natural or original distribution of P. aculeata in the Americas may have been more restricted than either that or present day distributions. Several authors have noted that the natural distribution of P. aculeata is difficult to ascertain (e.g. Isley, 1975; McVaugh, 1987; Woods, 1992). Extensive isolated pure stands of P. aculeata are found throughout southern USA, Mexico and Central America at seasonally flooded former lake bed sites, coastal estuaries or lagoons with deep black vertisols. P. aculeata is rarely found outside these sites, which are often highly disjunct, except as a putatively recent invader of roadsides, railway lines or irrigation channels, or where planted. Hughes (1989) has suggeste

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

2.05

Introduced to several countries.'...it has been introduced pantropically as an ornamental, hedging and fodder tree.'

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

3.01

'The establishment of extensive naturalized weedy populations, especially in Australia, has stimulated research into the biological control of this species … ' 'Parkinsonia aculeata has a widespread distribution in Africa, and is becoming naturalized in many areas'.

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

3.02

No evidence of being a garden weed

3.03

(1)AB: "P. aculeata is a spiny leguminous tree that is a weed in N. Australia. It blocks access to waterholes, shades out desirable vegetation and makes mustering of cattle difficult." (2) A weed of National Significance in Australia

(1)Woods, W. (1985) Bruchid seed beetles for control of Parkinsonia aculeata in Australia. Proceedings of the VI International Symposium on Biological Control of Weeds., 1985, pp.855-862, 27 ref. (2)http://www.ngia.com.au/np/2000No12/00-12.html

3.04

Invades mesic habitats and seasonal wetlands threatening waterbird habitats of continental significance [Australia]

http://www.anbg.gov.au/weeds/weeds.html

3.05

No evidence

4.01

(1) 'The petiole and primary rachis reduced, 10-30 mm long, and stoutly spinescent. ' (2)'...central axis 20 to 40 cm long, 2 to 3 mm wide ending in a short spine and edged on both sides…'

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.hear.org/pier/paacu.htm

4.02

AB: "Aqueous leachates (100%) from leaves of all tested species (including P. aculeata), except that of Pithecellobium dulce , decreased seed germination and vigour index of Parthenium hysterophorus ." [lab only, not indiciative of allelopathy in the field]

Dhawan, S. R.; Poonam Dhawan; Gupta, S. K. (2001) Allelopathic potential of leguminous plant species towards Parthenium hysterophorus L. (1) - effect of aqueous foliar leachates. Legume Research, 2001, Vol.24, No.4, pp.256-259, 24 ref.

4.03

No evidence

4.04

(1) Trees are not browsed by cattle or horses
(2) AB: Plantations, mostly of Parkinsonia aculeata and Prosopis juliflora, but also including Acacia nilotica, Atriplex halimus, A. nummularia, Cajanus cajan and Leucaena leucocephala are used as forage and are of considerable economic importance. Production data are presented for Faidherba [Acacia ] albida, P. aculeata and P. juliflora. 39 spp. introduced into arid zones are listed. (3)Not recognized as a fodder (fence post only) (4)Not recognized as a fodder (5)Is recognized as an animal fodder tree [conflicting information!] (6)Grazing is limited by the sharp spines

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.
(2) Lepape, M.-C. Browse in the Cape Verde Islands. A preliminary study. Editor: Houérou, H.N. Browse in Africa, 1980, pp.123-125 (3)http://www.fao.org/ag/AGP/AGPC/doc/Counprof/namibia.htm (4)http://www.echonet.org/tropicalag/aztext/azch4mul.htm (5)http://www.idrc.ca/library/document/092692/092692e.htm (6)http://www.agric.wa.gov.au/programs/app/weeds/parkinsonia.htm

4.05

No evidence

4.06

(1)'No pests and diseases of importance have been noted for P. aculeata. Pests recorded
Insect pests:
Enarmonia malesana [not economically important]
Icerya aegyptiaca [a scale insect that colonized nearly a hunfred genera of plants]
(2) This site lists 30 fungi species to be associated with P. aculeata. [most are saprophytic species, other parasitic species are not recognized pathogen]

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://nt.ars-grin.gov/fungaldatabases/all/FindRecOneFungusFrame.cfm

4.07

No evidence

4.08

The leaves appear shortly after rain, they fold up at night, and usually within a few days the tiny leaflets drop off, leaving the persistent rachises (midribs) to flutter like streamers in the wind. Eventually these fall off too, and accumulate like pine needles beneath the tree. [these growth charcteristics combined with dry habitat and dense stands = likely fire hazard]

http://www.floridata.com/ref/P/park_acu.cfm

4.09

P. aculeata is a small fast-growing, light-demanding tree

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

4.1

(1)tolerance of soil types is wide (2)Soil tolerances: clay; sand; loam; alkaline; acidic; well-drained

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://edis.ifas.ufl.edu/ST431

4.11

no evidence

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

4.12

(1)often forming thickets (2)often form single species stands

(1)http://www.hear.org/pier/paacu.htm (2)http://cgsc.biology.yale.edu/precolog.html

5.01

Fabaceae

5.02

Fabaceae

5.03

(1) 'In addition to its aggressive weedy tendencies, lack of nitrogen-fixing ability (Sprent, 1986) may limit the usefulness of the species …' '...and it does not fix nitrogen.'
(2)AB: Forty nitrogen fixing tree and shrub species, native or introduced to Pakistan, are discussed, and studies of the distribution and degree of nodulation of some of these (in Pakistan) are reviewed.(including Perkinsonia acultata [Parkinsonia aculeata])
(3) Besides being hardy, it has the added benefit of fixing nitrogen (Harris, S.C. 1982. Nitrogen fixation by tropical woody legumes: potential source of soil enrichment. Roskoski, J.P., J. Monano, C. van Kessel, G. Castilleja, and P.H. Graham, eds. Biological nitrogen fixation technology for tropical agriculture. Centro International de Agricultura Tropical. Cali, Colomabia. 447-454.).
(4) AB: Data are presented for 45 species (4 Mimosaceae, 8 Caesalpiniaceae, 33 Papilionaceae). Nodules were not found and could not be indicated in the Caesalpiniaceae (including P. aculeata) e

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International.
(2) Haque, S. M. S. (1990) Nitrogen fixing trees and shrubs of Pakistan and their role in soil improvement - a review. Commonwealth Forestry Review, 1990, Vol.69, No.4, pp.345-349, 19 ref.
(3) http://www.fs.fed.us/global/iitf/Parkinsonia%20aculeata.pdf
(4) Athar, M.; Mahmood, A. (1985) Qualitative study of the nodulating ability of legumes of Pakistan. List 3. Tropical Agriculture, UK, 1985, Vol.62, No.1, pp.49-51, 25 ref. (5)http://www.rala.is/rade/rade-Sinha.PDF

5.04

No evidence

6.01

'In Central America peak flowering is from February to March, with sporadic flowering thereafter.'

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

6.02

(1) 'Seedlings germinate over a wide temperature range,…' (2) About 25% of the light brown seeds germinate readily. The rest of the light brown seeds and all of the dark brown seeds have hard seed coats which must be scarified before they will germinate.

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2) http://www.floridata.com/ref/p/park_acu.cfm

6.03

(1) 'Natural hybrids have been described between P. aculeata and C. praecox (Ruiz and Pavón) Harms., a thorny arid zone species with a disjunct distribution spanning the arid regions of tropical and subtropical North, and South America (Carter, 1974b; Hawkins, 1996). The hybrids, which are unarmed, have been identified as a potential new agroforestry species (Hughes, 1989), although they may pose a novel and significant threat of weediness. ' (2) Morphometric, cytogenetic, geographical and ecological evidence for hybridization between Parkinsonia aculeata and Cercidium praecox is presented. Morphometric investigation using the character count procedure and cytogenetic observations confirm hybrid status. All diagnostic morphometric characters were intermediate in the hybrid. Both parents (2n = 28) show regular tetrad formation and pollen fertility greater than 94%. Hybrids have a chromosome number of 2n = 28 or 2n = 30, and display meiotic abnormalities including lagging chromosomes and micronucleus formatio

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)Hawkins-Julie-A {a}; Olascoaga-Laura-White; Hughes-Colin-E; Contreras-Jimenez-Jose-Luis-R; Mercado-Ruaro-Pedro. 1999. Investigation and documentation of hybridization between Parkinsonia aculeata and Cercidium praecox (Leguminosae: Caesalpinioideae). Plant-Systematics-and-Evolution. 216 (1-2): 49-68.

6.04

No information

6.05

(1) "On a farm where megachilid bees [species not named] are reared to pollinate lucerne, the bees preferred to forage for nectar on P. aculeata and did not forage on lucerne until 3 weeks after it started to flower ."

(1) Sihag, R. C. (1982) Effect of competition with Parkinsonia aculeata L. on pollination and seed production in Medicago sativa L. Indian Bee Journal, 1982, Vol.44, No.4, pp.89-90

6.06

Propagation of P. aculeata is generally by seed, either direct-sown or nursery-grown.

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

6.07

(1)Growth rate: fast (2)Parkinsonia is very rapid growing [minimum estimate for a fast growing woody shrub]

(1)http://edis.ifas.ufl.edu/ST431 (2)http://www.agric.wa.gov.au/programs/app/weeds/parkinsonia.htm

7.01

contaminated mud sticking to machinery, footware

http://www.weeds.crc.org.au/main/wom_parkinsonia.html

7.02

'...it has been introduced pantropically as an ornamental, hedging and fodder tree…'

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

7.03

'Weed: potential seed contaminant ' [but no products]

http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl?Parkinsonia+aculeata

7.04

no evidence that the seeds have any adaptations for wind dispersal such as wings or pappus. 'Pods are indehiscent, and have to be macerated in order to extract the seed.'

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

7.05

(1)Seeds transported by water, birds and animals. (2) The pods float and are spread by floods.

(1)http://www.hear.org/pier/paacu.htm (2)http://www.agric.wa.gov.au/programs/app/weeds/parkinsonia.htm

7.06

Seeds transported by water, birds and animals.

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

7.07

Seeds transported by water, birds and animals. Probably not - no evidence that the seeds have any means of attachment.

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

7.08

(1)one common name is HORSEBEAN [clearly implies consumption of pods by animals] (2)spread by birds and animals (both domestic and feral)

(1)http://www.anapsid.org/resources/plants-hn.html (2)http://www.weeds.crc.org.au/main/wom_parkinsonia.html

8.01

'Fruits indehiscent orange-brown glabrous pods, subterete, constricted and flattened between seeds. Seeds 2-8 per pod, 8-11 mm long, dark and light brown or grey mottled.' 'Seeding is prolific,…'.

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

8.02

(1) 'Pods are indehiscent, and have to be macerated in order to extract the seed.' 'Mahmoud and El-Sheikh (1981) noted two types of seed, light and darker seed. Light seed are water permeable and germinate freely, but dark seed require a sulphuric acid pre-treatment for 1 hour at 25°C in order to become permeable and germinate rapidly. Germination rates are improved by cold water soaking for three to six days (Webb et al., 1984), by manual scarification or by limited hot water treatment and maceration.' (2) Parkinsonia produces large numbers of seed pods. Many of the seeds are hard and will germinate years later, in some cases after long immersion in water. Parkinsonia produces large numbers of seed pods. Many of the seeds are hard and will germinate years later, in some cases after long immersion in water.

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International (2)http://www.agric.wa.gov.au/programs/app/weeds/parkinsonia.htm

8.03

Physical: “Mechanical removal by bulldozing, pulling with a tractor or grubbing gives effective control, especially where subsequent seedling growth can be controlled…” (Parsons and Cuthbertson, 1992)
Chemical: “Good control of mature trees also is possible with herbicides, basal bark or cut stump treatments usually giving better results than an overall spray. Apply a picloram + 2,4-D mixture or triclopyr in diesel oil, to the basal 75 cm of trunk, completely circling it and thoroughly drenching the bark. In cut stump treatments swab the whole of the butt with any of the herbicides mentioned as basal bark sprays, immediately after cutting. Allow the severed aerial growth to dry out and then burn. Alternatively, apply liquid or granular hexazinone concentrate to the soil surface close to the base of the stems. This material washed into the soil by subsequent rains slowly kills the shrubs.” (op. cit.) 

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

8.04

'Trees are browse-resistant, and withstand pruning and coppicing well.'

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

8.05

(1)Biological: Rhinacloa callicrates Herring (Hemiptera: Miridae) introduced into Queensland, Australia; under evaluation (2) Rhinacloa callicrates was thus considered safe, and was released across northern Australia. Rhinacloa callicrates established in Queensland but has not controlled P. aculeata.

(1)http://www.hear.org/pier/paacu.htm (2) Donnelly-Graham-P. 2000. Biology and host specificity of Rhinacloa callicrates Herring (Hemiptera: Miridae) and its introduction and establishment as a biological control agent of Parkinsonia aculeata L. (Caesalpiniaceae) in Australia. Australian-Journal-of-Entomology. 39 (2): 89-94.


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