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

Samanea saman (Albizia saman)

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

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

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

Y

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

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

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

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

N

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

4

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

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

8.05

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

y=-1, n=1

Total score:

4

Source

Notes

1.01

Did not find evidence for this species having any cultivars.

1.02

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.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

'…in Hawaii a popular shade and street tree now naturalized in disturbed areas,… .' 2)naturalized in Hawaii, Puerto Rico, and the Virgin Islands

1.03

Did not find any evidence on this species having weedy, subspecies, cultivars or varieties.

2.01

Durr-P-A. 2001. The biology, ecology and agroforestry potential of the raintree, Samanea saman (Jacq.) Merr.Agroforestry-Systems. [print]; 51 (3): 223-237.

'Samanea saman (Jacq.) Merr. (syn. Albizia saman (Jacq.) F. v. Muell.) is a large tree, native to tropical America, which has now become widespread throughout the humid and subhumid tropics.'

2.02

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

2.03

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

Altitude range is 0 -1500 m. It grows in evergreen forests, savanna habitats as well as dry forests. Monkey-pod grows in a broad annual rainfall range of 640 to 3810 mm

2.04

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

'…in Hawaii a popular shade and street tree now naturalized in disturbed areas,… .'

2.05

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

Introduced in many places throughout the tropics and the subtropics.

3.01

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

'Native to Mexico to Peru and Brazil, now … in Hawaii … naturalized in disturbed areas, … .'

3.02

Did not find evidence for this species being a weed.

3.03

Did not find evidence for this species being a weed.

3.04

This plant has become abundant in certain disturbed habitats, but we could find no instances of organized control programs or evidence of strong interest in removing this plant. It was generally thought to be beneficial by providing shade, and keeping soil moist for longer periods of time in dryland habitats. The massive size and N-fixing properties of these trees make it likely that they effect major changes in the natural habitats in which they grow, so in this sense, it might be considered an environmental weed. Note however, that it has already been given extra points for being a N-fixer (question 5.03). Trivia: the tree house in Walt Disney's "Swiss Family Robinson" was built in a rain tree

3.05

There is no evidence of a congeneric weed, but if you consider the genus 'Albizia' (which was the old genus of Samanea - species of both genera are very similar in terms of habit) then there are congeneric weedy species. Albizzia julibrissin - listed as weedy in 'Weeds of the United States and their control' 1987 by Lorenzi and Jefferey. Also, formerly called Pithecellobium saman. Pithecellobium dulce is a weed.

4.01

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

The species does not produce any spines, thorns or burrs.

4.02

Magnus K. E. & S. E. Seaforth. 1965. Samanea saman Merrill: The rain tree. A review. Tropical Science 7(1): 6-11.

'Especially during the rainy season a sap exudes and drips from injured tree. Through its contact with pasture grasses growing beneath the tree, this sap kills these grasses in localized places only. … The effects are not lasting in soil because grass would grow back again in previously affected spots.

4.03

Did not find any evidence that the species is parasitic

4.04

Durr-P-A. 2001. The biology, ecology and agroforestry potential of the raintree, Samanea saman (Jacq.) Merr.Agroforestry-Systems. [print]; 51 (3): 223-237.

'The tree provides excellent protective shade, and produces highly palatable pods that are suitable as a dry season feed supplement.'

4.05

(1) Anon, 1990. Toxicity of plants to cattle in the northern region of the State of Goias. Informativo-Tecnico-Empresa-Goiana-de-Pesquisa-Agropecuaria. 1990, No. 2, 29 pp.; 14 ref. (2) Magnus K. E. & S. E. Seaforth. 1965. Samanea saman Merrill: The rain tree. A review. Tropical Science 7(1): 6-11.

(2) 'This is a fortunate circumstance, since these seeds have been found to contain a toxic alkaloid, which may account for the occasional deaths of cattle which graze near the tree.'

4.06

The website lists the following fungi on S. saman (those that are pathogenic to economic plants (like . Botryodiplodia) have a wide host range.
Botryodiplodia theobromae: Cuba - 8361, 8557
Cercospora samaneae: Cuba - 8361, 8557; Venezuela - 786
Cladosporium oxysporum: Cuba - 8361, 8557
Fomes sp.: Fiji - 7283
Hypomyces haematococcus: HI - 94, 1710
Hypoxylon rubiginosum: Sierra Leone - 8557
Hypoxylon stygium: Sierra Leone - 8557
Hypoxylon truncatum: Sierra Leone - 8557
Meliola aethiops var. minor: Sierra Leone - 8557
Microstoma pithecellobii: Cuba - 8361; Venezu
Phyllosticta pithecolobii: HI - 1710
Phyllosticta sp.: Cuba - 8361, 8557
Polyporus ostreiformis: Philippines - 7101
Pythium sp.: HI - 1710
Tricholoma sp.: Philippines - 7101

http://nt.ars-grin.gov/fungaldatabases/all/FindRecOneFungusFrame.cfm

4.07

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

The sticky sweet-flavored pulp of the pods is often eaten by children and can be used in fruit drinks.

4.08

no evidence

4.09

http://www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

Seedlings and mature trees are intolerant of shade

4.1

CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. http://www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

grows well on a wide variety of soils when planted and can withstand seasonal flooding

4.11

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

The species is a tree and not a vine. No evidence of it having a smothering habit.

4.12

canopy is relatively open and high. Individual plants are large but generally do not form dense, continuous stands

Did not find any evidence on the ability of the species to form monocultures that exclude others.

5.01

5.02

5.03

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

A tree species that has the ability to fix nitrogen.

5.04

0

6.01

Did not find any evidence on reproductive failure.

6.02

Did not find any evidence on non-viability of seeds.

6.03

No references on natural hybridization.

6.04

No information.

6.05

Janzen, D.H. 1983. Costa Rican natural history. The university of Chicago Press. Chicago.l http://www.hort.purdue.edu/newcrop/duke_energy/Samanea_saman.html

is an important honey plant for bees

6.06

http://www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

started from seed.

6.07

No information.

7.01

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

Although this species is a common avenue tree in many places where it has been introduced, the seeds are not sticky and nor do they have any hooks or burrs. Also the seeds are relatively large legume seeds. Hence it is unlikely that it will be dispersed unintentionally by people.

7.02

Widely grown for parks and cattle

7.03

Seed are relatively large (8-11mm X 5-7.5mm) and it is unlikely that it will be introduced as a produce contaminant.

7.04

7.05

7.06

Janzen, D.H. 1983. Costa Rican natural history. The university of Chicago Press. Chicago.l http://www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

'Peccaries eat fruits but grind up the seeds in the process.' Natural dissemination is by birds and rodents

7.07

Janzen, D.H. 1983. Costa Rican natural history. The university of Chicago Press. Chicago.l

'A few are carried off by rodents and the fruit pulp and seeds are partly or completely eaten (ground up).'

7.08

(1) Pasicolan, P. N.; Ramos, M. T.; Menz. 1998. Imperata Project Paper - Improving Smallholder Farming Systems in Imperata Areas of Southeast Asia, No.1998/2, iii + 11 pp., 4 ref. (2)Janzen, D.H. 1983. Costa Rican natural history. The university of Chicago Press. Chicago.l

(1) 'Grazing animals have been observed feeding on seed pods of the tree, and when the indigestible seeds are excreted by the animals, the seeds germinate in the fertile medium of the animal dung.' (2) A few are eaten by tapirs and some seeds survive the trip through the animal to be dispersed'.

8.01

http://www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

pod contains from 5 to 20 seeds, each seed 13 mm wide. Produces copious pods.

8.02

Janzen, D.H. 1983. Costa Rican natural history. The university of Chicago Press. Chicago.l http://www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

According to this paper the pods generally fall to the ground and rot or the seeds may be carried away by rodents, tapirs and cattle. Seeds are hard coated and long lived (legume).

8.03

http://www.na.fs.fed.us/spfo/pubs/silvics_manual/volume_2/pithecellobium/saman.htm

The species does not seem to be considered as a weed - (hence) did not find any reference on efforts to chemically control the specie, however, it was noted that the plant is easily damaged by herbicides and extreme caution must be used when spraying around these plants.

8.04

No information. Large trees are likely to survive fire but no information on smaller trees response or response to cutting. It is common practice to move large trees to new landscaping by cutting off all branches and digging up a relatively small root ball. The trunk and root ball are planted at a new location where they regrow into healthy trees. Suggests that they can tolerate mutilation.

8.05

Biological control of weeds by Julien and Griffith.

Did not find any evidence on the biocontrol of this species.