Pacific Island Ecosystems at Risk (PIER)


Pachira aquatica


RISK ASSESSMENT RESULTS: Low risk, score: -6


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

Pachira aquatica (Malabar Chestnut, Guiana Chestnut, Saba nut )

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

n

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

n

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

n

3.05

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

n=0

n

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

n

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

n

4.09

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

y=1, n=0

y

4.1

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

y=1, n=0

4.11

Climbing or smothering growth habit

y=1, n=0

n

4.12

Forms dense thickets

y=1, n=0

n

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

y

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

y

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

n

8.02

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

y=1, n=-1

n

8.03

Well controlled by herbicides

y=-1, n=1

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:

-6

Supporting data:

Source

Notes

1.01

No evidence

1.02

No evidence

1.03

No evidence

2.01

(1) 'Origin: The Malabar chestnut is native to an area from southern Mexico to Guyana and northern Brazil. ' (2) 'In the wild, Pachira aquatica is a wetland tree that grows in freshwater swamps associated with tropical estuaries. It often grows alongside rivers, where its branches arch out over the water.'

(1)http://www.crfg.org/pubs/ff/malabar.html (2)http://www.floridata.com/ref/P/pach_aqu.cfm

2.02

2.03

Hardiness Range: 10A - 11 [natural range restricted to swamp habitats]

http://www.hortpix.com/pc3015.htm

2.04

(1) 'Origin: The Malabar chestnut is native to an area from southern Mexico to Guyana and northern Brazil. ' (2) 'In the wild, Pachira aquatica is a wetland tree that grows in freshwater swamps associated with tropical estuaries. It often grows alongside rivers, where its branches arch out over the water.'

(1)http://www.crfg.org/pubs/ff/malabar.html (2)http://www.floridata.com/ref/P/pach_aqu.cfm

2.05

(1)In California the growth is more like 10 to 15 ft. tall with a spread of 8 to 10 feet. (2)It is cultivated in many tropical regions, including Hawaii and Southern California. (3)Introduced to China

(1)http://www.crfg.org/pubs/ff/malabar.html (2)http://www.floridata.com/ref/P/pach_aqu.cfm (3)ET:
Identification of the fungal diseases in Pachira macrocarpa .
AU: Xi PingGen; Qi PeiKun; Jiang ZiDe
SO: Journal of South China Agricultural University, 2000, Vol.21, No.4, pp.30-32, 10 ref.

3.01

No evidence

3.02

No evidence

3.03

No evidence

3.04

No evidence

3.05

No evidence

4.01

No evidence

http://www.crfg.org/pubs/ff/malabar.html

4.02

No evidence

4.03

No evidence

4.04

'Young leaves and flowers are cooked and used as a vegetable.'

http://www.crfg.org/pubs/ff/malabar.html

4.05

'Young leaves and flowers are cooked and used as a vegetable.'

http://www.crfg.org/pubs/ff/malabar.html

4.06

(1)The following 4 fungi were listed to ba associated with P. aquatica
Cercospora pachirae: Brazil - 34636 [specialist but no economic importance]
Colletotrichum sp.: Brazil - 34636 [generalist]
Curvularia sp.: FL - 1 [generalist]
Phaeoramularia sp.: Brazil - 34636 [saprophytic]
(2)Phomopsis macrocarpae sp. nov. [specialist but no economic importance], Phomopsis durionis [specialist but no economic importance], Botryodiplodia theobromae [generalist], Colletotrichum gloeosporioides (Glomerella cingulata) [generalist], Pestalotiopsis gracilis [specialist, known from avocado, but not a serious pathogen], Trichothecium roseum [generalist], Curvularia lunata [Cochliobolus lunatus ] [generalist] and Alternaria tenuissima [generalist].

(1)http://nt.ars-grin.gov/fungaldatabases/all/FindRecOneFungusFrame.cfm (2)ET: Identification of the fungal diseases in Pachira macrocarpa .
AU: Xi PingGen; Qi PeiKun; Jiang ZiDe
SO: Journal of South China Agricultural University, 2000, Vol.21, No.4, pp.30-32, 10 ref.

4.07

'Young leaves and flowers are cooked and used as a vegetable.'

http://www.crfg.org/pubs/ff/malabar.html

4.08

Probably not - a wetland species.- an evergreen tree.

http://www.crfg.org/pubs/ff/malabar.html

4.09

(1)prefers partial shade or partial sun to full sun (2)Sun Exposure: Sun to Partial Shade, Light Shade
(3) AB: "The photosynthetic activities of 10 foliage plants (all more than or equal to 2-years-old), grown under 40 or 80% shade, were investigated in a plastic house." [can be grown under 80% shade] 

(1)http://www.hortpix.com/pc3015.htm (2)http://plantsdatabase.com/go/56220/
(3) AU: Park SoHong; Lee YongBeom (1997) Effect of light acclimatization on photosynthetic activity of foliage plants. Journal of the Korean Society for Horticultural Science, 1997, Vol.38, No.1, pp.71-76, 36 ref.

4.1

(1) 'Soils: Malabar chestnuts are not overly fussy about soil as long as it is well drained. ' (2)Soil Requirements: Moderately fertile, well-drained soil

(1)http://www.crfg.org/pubs/ff/malabar.html (2)http://www.floridagardener.com/pom/pachira.htm

4.11

A tree

http://www.hortpix.com/pc3015.htm

4.12

No evidence

5.01

In the wild, Pachira aquatica is a wetland tree that grows in freshwater swamps associated with tropical estuaries. It often grows alongside rivers, where its branches arch out over the water.' [not truly aquatic]

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

5.02

'The Malabar chestnut is a very showy evergreen tree with greenish bark that can grow to 60 ft. in the tropics.'

http://www.crfg.org/pubs/ff/malabar.html

5.03

No evidence

5.04

Tree

6.01

No evidence

http://www.crfg.org/pubs/ff/malabar.html

6.02

'AB: Seed flotation, postflooding germination and initial height and expansion rates of seedlings of six terra firme (upland forest), i.e. Anacardium excelsum , Calophyllum longifolium , Dipteryx panamensis , Gustavia superba , Tabebuia rosea and Virola surinamensis , and six seasonally flooded forest (SFF) species, i.e. Carapa guianensis , Pachira aquatica , Pentaclethra macroloba , Prioria copaifera , Pterocarpus officinalis and Pterocarpus sp., from Panama were examined as indicators of their potential for dispersal by water. Compared to terra firme species, SFF species had larger seeds with greater volumes and lower seed specific weights, resulting in greater buoyancy. Across all species, seed specific weight was negatively correlated with initial flotation. After 60 days in water, an average of 53% of the seeds of SFF species remained buoyant. In contrast, no seeds of the terra firme species remained buoyant after 15 days. On average more than half the seeds of SFF species germinated after 60 days

ET: Seed flotation and postflooding germination in tropical terra firme and seasonally flooded forest species.
AU: Lopez, O. R.
SO: Functional Ecology, 2001, Vol.15, No.6, pp.763-771, many ref.

6.03

No evidence

6.04

Don't know

6.05

(1)Mammal pollinated. [Specific animal not mentioned]. (2)Flowers stay open for one night, and attract bats - interesting to observe. [floral morphology also implies specialist pollination]

(1)http://www.esapubs.org/archive/mono/M073/004/appendix-A.htm (2)http://plantsdatabase.com/go/56220/

6.06

'Propagation: The tree may be propagated by seed and cuttings, and probably by air-layering. ' [No evidence of vegetative propagation in the wild.]

http://www.crfg.org/pubs/ff/malabar.html

6.07

Fast growing [minimum for a large, fast growing tree; usually is is probably > 4 years]

http://www.fukubonsai.com/3a3d.html

7.01

Probably not - relatively large fruit and seeds.

http://www.crfg.org/pubs/ff/malabar.html

7.02

'Guiana chestnut is grown both for tropical effect and for its edible nuts. It can also be potted up as a houseplant. The nuts taste sort of like peanuts. They are harvested when the seed pods burst and eaten raw, roasted, or fried. They also can be ground into a flour for baking bread. The young leaves and flowers may be cooked and used as a vegetable.'

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

7.03

Probably not - relatively large fruit and seeds.

http://www.crfg.org/pubs/ff/malabar.html

7.04

'Fruit: The five-valved fruit of Malabar chestnut is an ovoid, woody green pod which may reach 4 to 12 inches in length and 2 to 2-1/2 inches in diameter, bearing some resemblance to kapok or silk floss seed pods. The tightly packed seeds (nuts) inside enlarge until the pod bursts and the seed fall to the ground. The rounded seeds are without floss and 1/2 inch or larger in diameter.'

http://www.crfg.org/pubs/ff/malabar.html

7.05

(1)Seed flotation, postflooding germination and initial height and expansion rates of seedlings of six terra firme (upland forest), i.e. Anacardium excelsum , Calophyllum longifolium , Dipteryx panamensis , Gustavia superba , Tabebuia rosea and Virola surinamensis , and six seasonally flooded forest (SFF) species, i.e. Carapa guianensis , Pachira aquatica , Pentaclethra macroloba , Prioria copaifera , Pterocarpus officinalis and Pterocarpus sp., from Panama were examined as indicators of their potential for dispersal by water. Compared to terra firme species, SFF species had larger seeds with greater volumes and lower seed specific weights, resulting in greater buoyancy. Across all species, seed specific weight was negatively correlated with initial flotation. After 60 days in water, an average of 53% of the seeds of SFF species remained buoyant. In contrast, no seeds of the terra firme species remained buoyant after 15 days. On average more than half the seeds of SFF species germinated after 60 days, while f

(1)Lopez, O. R. 2001. Seed flotation and postflooding germination in tropical terra firme and seasonally flooded forest species. Functional Ecology, , Vol.15, No.6, pp.763-771 (2)http://www.ambergriscaye.com/fieldguide/bzplants.html

7.06

Probably not - seeds enclosed in hards woody capsule.

7.07

Probably not - no evidence of propagules have any means of attachment.

7.08

Nuts are possibly ingested by large animals

8.01

The large green pods hold 20 to 30 nuts and split open when ripe. [large seeds.]

http://www.fruitlovers.com/fruittreedescriptions.html

8.02

After 60 days in water, an average of 53% of the seeds of SFF species remained buoyant. In contrast, no seeds of the terra firme species remained buoyant after 15 days. On average more than half the seeds of SFF species germinated after 60 days, while for the terra firme species, germination was reduced by 50% after 13 days. [rapid changes in large seeds implies no dormancy mechanism

Lopez, O. R. 2001. Seed flotation and postflooding germination in tropical terra firme and seasonally flooded forest species. Functional Ecology, , Vol.15, No.6, pp.763-771 (2)http://www.ambergriscaye.com/fieldguide/bzplants.html

8.03

No evidence that the species is being controlled for.

8.04

When the leaves grow too big you just trim them off. The new bud will start popping out a few days later.

http://www.alisainter.com/money_tree.htm

8.05

Don’t know


Need more info? Have questions? Comments? Information to contribute? Contact PIER!


[ Return to PIER homepage ] [Risk assessment page]


This page updated 3 November 2005