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

Cassia x nealiae ; rainbow shower tree (sterile hybrid between C. javanica and C. fistula)

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

n

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

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

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

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

n

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

n

6.05

Requires specialist pollinators

y=-1, n=0

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

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

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

n

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

8.05

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

y=-1, n=1

Total score:

-8

Source

Notes

1.01

No evidence

1.02

1.03

No evidence

2.01

It is native to South-East Asia and is widely planted throughout the tropics as an ornamental and roadside tree, and has become naturalized in numerous tropical countries.

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

2.02

2.03

(1)Approximate limits north to south: 4°N to 21°S. Altitude range: 0 - 400 m (2)Hardiness range 10B -11[For C. javanica]

(1)CAB International, 2000. Forestry Compendium Global Module. Wallingford, UK: CAB International. (2)http://www.hortpix.com/pc937.htm

2.04

Hawai‘i

2.05

Hawai‘i

3.01

No evidence

3.02

No evidence

3.03

No evidence

3.04

No evidence

3.05

C. eremophila is a principle weed in Australia, C. absus and C. laevigata are common weeds in Zimbabwe and the U.S. respectively. [Note: The weedy "Cassias" are now in the genus Senna because of important differences from the "true" Cassias]

Holm et al. 1997. An electronic atlas of weeds and invasive species. CD-ROM database Version 1.0

4.01

No evidence

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

4.02

No evidence

4.03

No evidence

4.04

No information

4.05

No evidence

4.06

Cercosporidium cassiae, Hypoxylon rubiginosum, Macrovalsaria megalospora Monochaetinula terminaliae, Phyllachora canafistulae were found to be associated with Cassia javaninca. [For C. javanica, Did not find the above fungi to be recognized pests].

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

4.07

No evidence

4.08

No information regarding fire ecology.

4.09

It is shade tolerant. [based on C. javanica; actually, I doubt if C. xnealiae is shade tolerant but since it only grows from cuttings (no seedlings) it is possible the that cutting have enough stored energy to tolerate shade for some time]

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

4.1

Soil: Rich, medium texture [C. javanica]

http://www.treefarm.com.au/Cassia_javanica_x.htm

4.11

small tree

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

4.12

No evidence

5.01

small tree

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

5.02

small tree

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

5.03

legume [C. javanica]

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

5.04

small tree

6.01

[C. javanica]

Bose, T.K., Das, P. and Maiti. G. G. 1998. Trees of the world. Vol 1. Regional plant resource center. India.

6.02

x nealiae is a sterile hybrid

6.03

No invormation [it is probably male-sterile]

6.04

sterile

6.05

No information

6.06

a non-spreading tree, propagate by cuttings but this is not natural

6.07

R. Criley, UH Department of Horticulture, personal communication [cuttings, no natural reproduction]

7.01

Probably not - did not find evidence on the propagules having any means of attachment.

7.02

Probably yes as it is an attractive tree grown for ornamental purposes in gardens and along roadsides.

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

7.03

Probably not as it is a legume and may have relatively big seeds.

7.04

sterile

7.05

sterile

7.06

sterile

7.07

sterile

7.08

sterile

8.01

sterile

8.02

sterile

8.03

No evidence that the species is being controlled for.

8.04

No information

8.05

Don’t know.