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

Cryptostegia madagascariensis Bojer (Madagascar rubber vine)

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

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

n

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

y

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

y

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

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

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

y

4.11

Climbing or smothering growth habit

y=1, n=0

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

y

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

y

6.05

Requires specialist pollinators

y=-1, n=0

n

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

2

6.07

Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1

See left

n

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

n

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

y

7.04

Propagules adapted to wind dispersal

y=1, n=-1

y

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

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

1

Total score:

13

Notes

Source

1.01

no evidence

1.02

"C. grandiflora and C. madagascariensis, are widely cultivated and have become pests in places where they are introduced, including Australia, where C. grandiflora has been called one of their worst weeds, and in Florida, where C. madagascariensis is considered a category II weed by the Florida Exotic Pest Plant Council."

http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

1.03

no evidence

2.01

"Cryptostegia madagascariensis is distributed along the whole of the western part of Madagascar, mostly in western phytogeographical domain but is also found in the Toliara region in southwestern domain."

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

2.02

2.03

" It has been found from sea level up to 700 m alt., usually in full sun. It grows in dry forest (e.g. Didiereaceae, Euphorbia), savannah, tsingy, disturbed grazed grassland, on lateritic soil and sand, often on river beds."

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

2.04

"Cryptostegia madagascariensis is distributed along the whole of the western part of Madagascar, mostly in western phytogeographical domain but is also found in the Toliara region in southwestern domain."

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

2.05

(1) Florida; Puerto Rico; (2) Hawaii

(1) USDA, NRCS. 2004. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA. (2) http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

3.01

"C. grandiflora and C. madagascariensis, are widely cultivated and have become pests in places where they are introduced, including Australia, where C. grandiflora has been called one of their worst weeds, and in Florida, where C. madagascariensis is considered a category II weed by the Florida Exotic Pest Plant Council."

http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

3.02

no evidence

3.03

no evidence

3.04

(1)"C. madagascariensis is present in southern Florida in the Keys and in a few counties on the coast of south western Florida (PLANTS 2001). C. madagascariensis is listed by the Florida Exotic Pest Plant Council as a category II pest plant (FLEPPC 1999). These are species that have shown a potential to disrupt native plant communities." (2)Environmental weed of Western Australia and Northern Territory (3)Class 3 declared species - sale prohibited by Queensland’s Land Protection

(1)http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm (2)Randall, R. 2001. Garden thugs, a national list of invasive and potentially invasive garden plants. Plant Protection Quarterly 16:138-171. (3)http://www.weeds.crc.org.au/documents/backyard_beauties_bushland_bullies_040903_.pdf

3.05

rubber vine (Cryptostegia grandiflora) is a weed in Australia

Tomley, A. J. (1995) The biology of Australian weeds. 26. Cryptostegia grandiflora R. Br. Plant Protection Quarterly, 1995, Vol. 10, No. 4, pp. 122-130, 50 ref.

no description of these traits

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

4.01

no evidence

4.02

no evidence

4.03

The major impact on primary industry is through the loss of cattle production from infested areas and subsequent control costs. As rubber vine invades open pasture, grass growth decreases as rubber vine cover increases (Vitelli 1995) and the weed utilises soil moisture and this translates directly into a loss of carrying capacity.

http://www.nrme.qld.gov.au/pests/psas/pdfs/Rubbervine.pdf

4.04

Feeding tests have shown the leaves of rubber vine to be toxic to cattle, horses, goats and sheep (McGavin 1969, Everist 1974). Horses are particularly susceptible; toxic effects follow after consumption of only 0.03-0.06% of their body weight (McGavin 1969, Cook et al. 1990). [effects found in feeding trials, not in nature - it seems to be unpalatable under normal conditions, see 4.04]

http://www.nrme.qld.gov.au/pests/psas/pdfs/Rubbervine.pdf

4.05

Acrostalagmus aphidum: Puerto Rico; Virgin Islands [generalist]
Hemileia cryptostegiae: Madagascar - [no evidence of economic importance]
Maravalia cryptostegiae: Madagascar - [no evidence of economic importance; but was introduced to Australia successfully established to control C. grandiflora; which is a crop in certain regions to harvest its latex for rubber production]
Scopella lombiroensis: Madagascar [no evidence of economic importance]

Farr, D.F., Rossman, A.Y., Palm, M.E., & McCray, E.B. (n.d.) Fungal Databases, Systematic Botany & Mycology Laboratory, ARS, USDA. Retrieved July 7, 2004, from http://nt.ars-grin.gov/fungaldatabases/

4.06

(1) "Contact with all parts of the plant can cause dermatitis (Hardin and Arena 1974)."
(2) Its poisonous properties have sometimes been utilised forcommitting suicide for religious reasons (3)The milky sap of this ornamental vine causes a severe dermatitis. If the dust of dried parts is inhaled, irritation to the eyes, nose and throat can occur accompanied by swelling.

(2) Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf (3)http://www.allergenica.com/Details.asp?PLANTID=52

4.07

no evidence [grandiflora forms thickets that can be burned, but no evidence for madagascariensis]

4.08

"It has been found from sea level up to 700 m alt., usually in full sun. It grows in dry forest (e.g. Didiereaceae, Euphorbia), savannah, tsingy, disturbed grazed grassland, on lateritic soil and sand, often on river beds." [probably not, only found in places with ample sun exposure]

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

4.09

"It grows... on lateritic soil and sand, often on river beds." [yes, lateritic soil is nutrient poor, rich of clay (2)]

(1) Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf
(2) http://www.acad.carleton.edu/curricular/GEOL/classes/geo258/studentswork/Converse.html

4.1

"Woody liana to shrub with scrambling branches, usually 2-3 m high and self-supporting but sometimes climbing up to 10 m high"

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

4.11

impedes access of stock to water and hinders mustering. [grandiflora; don't know if madagascariensis does the same]

http://www.nrme.qld.gov.au/pests/psas/pdfs/Rubbervine.pdf

4.12

"It has been found from sea level up to 700 m alt., usually in full sun. It grows in dry forest (e.g. Didiereaceae, Euphorbia), savannah, tsingy, disturbed grazed grassland, on lateritic soil and sand, often on river beds."

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

5.01

"Woody liana to shrub with scrambling branches, usually 2-3 m high and self-supporting but sometimes climbing up to 10 m high"

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

5.02

Asclepiadaceae

5.03

"Woody liana to shrub with scrambling branches, usually 2-3 m high and self-supporting but sometimes climbing up to 10 m high"

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

5.04

"C. madagascariensis is present in southern Florida in the Keys and in a few counties on the coast of south western Florida (PLANTS 2001). C. madagascariensis is listed by the Florida Exotic Pest Plant Council as a category II pest plant (FLEPPC 1999). These are species that have shown a potential to disrupt native plant communities." [invade natural habitat]

http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

6.01

"Cryptostegia spp. can propagate by seeds, which are approximately 95% viable "

6.02

AB: The genus Cryptostegia R. Br. comprises two species, both of which are endemic to Madagascar. One species, C. grandiflora Roxb. ex R. Br., is widely naturalised in tropical regions of the world. The other species, C. madagascariensis Bojer ex Decne., comprises three varieties, of which C. madagascariensis var. glaberrima (Hochreutiner) J. Marohasy and P. Forster is a new combination [.tbd. C. glaberrima] and C. madagascariensis var. septentrionalis J. Marohasy and P. Forster is newly described. Interspecific hybrids occur in a narrow zone where the two species are sympatric.

http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

6.03

Rubber vine is insect pollinated but and in Queensland pollination has not been observed, although viable seed is produced (Tomley 1995a). [chracteristics of C. grandiflora]

http://www.nrme.qld.gov.au/pests/psas/pdfs/Rubbervine.pdf

6.04

(1)Xylocopa spp. (carpenter bees); Batocnema coquereli (hawkmoth); Madagascar Hippotion saclavorum (hawkmoth); Nephele comma (hawkmoth)
[1 carpenter bee and 3 hawkmoths were recorded as pollinators] (2)flower structure restricts the suite of available pollinators

(1)http://www.uni-bayreuth.de/departments/planta2/research_wgl/pollina/as_pol_d.html (2)http://www.nrme.qld.gov.au/pests/psas/pdfs/Rubbervine.pdf

6.05

no evidence

6.06

(1) "Plants can begin to reproduce (flowering) after about 200 days and seeds remain viable for approximately 12 months (Russell 2001)." [description of Cryptostegia species as a whole]
(2) In Haiti, plants have been shown to flower at 5 to 7 months of age, when supplied with continuous water and grown as a commercial rubber crop (Symontowne 1943). Curtis (1946) recorded plant flowering 3 months after transplanting grafts in Haiti. First flowering under Queensland conditions (Charters Towers) can be within 250 days of germination with good rain on a sandy alluvial or heavy clay loam soil (Fig. 5) but is more usually 400-450 days after germination irrespective of soil type. (Curtis (1946) found the average time for fruit development from flowers to ripeopen fruit was 173 days. [description of Cryptostegia grandiflora]

(2) http://www.nrme.qld.gov.au/pests/psas/pdfs/Rubbervine.pdf

6.07

no evidence

7.01

"C. grandiflora and C. madagascariensis, are widely cultivated"

http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

7.02

no evidence

7.03

(1) "Follicles (5-)7-9 × 1-3 cm, glabrous to finely pubescent. Seeds 5-8 mm long; hairs 2-3 cm long.
(2) "Numerous seed with tufts of silky hairs help disperse the seeds in the wind.

(1) Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf
(2) http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

7.04

(1)Numerous seed with tufts of silky hairs help disperse the seeds in the wind.(2)often on river beds [habitat provides opportunity for floating seeds]

(1)http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm (2)Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

7.05

"Follicles (5-)7-9 × 1-3 cm, glabrous to finely pubescent. Seeds 5-8 mm long; hairs 2-3 cm long."

Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

7.06

no evidence

7.07

no evidence of ingestion

7.08

(1) Curtis (1946) also found of 1100 plants per hectare produced 15 fruits per plant per annum [1.65 fruit per square meter], while densities of 12000-29000 plants per hectare produced an average of 1 fruit per plant per annum [0.34- 0.83 fruits per square meter]. Curtis (1946) found the average time for fruit development from flowers to ripe open fruit was 173 days. The average seed weight was 9 mg with 668 seeds per fruit while 340-840 seeds per fruit have been recorded in Charters Towers (Vitelli 1987 unpublished report). A study in Haiti demonstrated that 3000 grafted Cryptostegia grandiflora plants per acre produced 8,061,000 flowers per acre per year and 182,700 fruit per acre per year (a flower to fruit ratio of 44:1) but in Queensland the flower to fruit ratio varies between around 6 to 150:1 depending on rainfall and soil type [description of C. grandiflora, 116 to 1386 seeds per square meter]
(2)"Follicles (5-)7-9 × 1-3 cm, glabrous to finely pubescent. Seeds 5-8 mm long; hairs 2-3 cm long."the rub

(2) Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdf

8.01

AB: "In the field, the most rapid decline in viability occurred under natural rainfall conditions, i.e. with no viable rubber vine seeds remaining in the soil seed bank after one year, irrespective of the burial depth. In contrast, viability of seed lots under conditions where rainfall was excluded averaged 68, 29 and 0% after 1, 2 and 3 years, respectively. Under dry storage, viability of 1-year-old seed was extremely high (99%) and not significantly different to that of freshly collected seed. In comparison, viability of 9- and 11-year-old seeds averaged 87%, and only 20% of 20-year-old seeds remained viable. Almost all viable seeds had sufficient vigour to develop into seedlings, irrespective of their age."
[description of a congeneric species, C. grandiflora. Probably no; seed viability decline rapidly in field condition]

Bebawi, F. F. , Campbell, S. D. , Lindsay, A. M. (2003) Effects of burial and age on viability of rubber vine (Cryptostegia grandiflora) seeds. Plant Protection Quarterly, 2003, Vol. 18, No. 4, pp. 147-151, 13 ref.

8.02

(1) Probably yes, several herbicides successfully control rubber vine (C. grandiflora, an invasive congeneric species)
(2) Chemical control: A variety of chemicals listed by Australia includes: Grazon DS, Banvel, Brushoff, Tordon, Velpar, Graslan, and 2, 4-D. In Hawai'i, Garlon has be used in cut stump treatments as well as mechanical removal.

(2) http://www.hear.org/starr/hiplants/reports/pdf/cryptostegia_spp.pdf

8.03

(1) " It has been found from sea level up to 700 m alt., usually in full sun. It grows in dry forest (e.g. Didiereaceae, Euphorbia), savannah, tsingy, disturbed grazed grassland, on lateritic soil and sand, often on river beds." [probabaly yes, grow in dry, fire-prone habitats]
(2) AB: " Exotic shrubs are significant invaders of the tropical woodlands of northern Australia. They cause problems for pastoral industries and are likely to induce significant change in woodland communities. A single fire in the middle of the dry season affected the survival and vegetative growth of two important shrub species, Cryptostegia grandiflora and Ziziphus mauritiana, at a site in Queensland. The fire killed about 96% of small plants (height < 100 cm), 80% of medium-sized plants and 45% of large plants (height > 200 cm) of C. grandiflora. However, only about 10% of small Z. mauritiana were killed. Most plants of Z. mauritiana resprouted vigorously within three months of the fire. Effects on the vegetative phenology of C. gr

(1) Klackenberg, J. (2001) Revision of the genus Cryptostegia R. Br. (Apocynaceae, Periplocoideae). Adansonia, 2001, Vol. 23, No. 2, pp. 205-218, 20 ref. URL: http://www.mnhn.fr/publication/adanson/a01n2a3.pdfExotic shrubs are significant invaders of the tropical woodlands of northern Australia. They cause problems for pastoral industries and are likely to induce significant change in woodland communities. A single fire in the middle of the dry season affected the survival and vegetative growth of two important shrub species, Cryptostegia grandiflora and Ziziphus mauritiana, at a site in Queensland. The fire killed about 96% of small plants (height < 100 cm), 80% of medium-sized plants and 45% of large plants (height > 200 cm) of C. grandiflora. However, only about 10% of small Z. mauritiana were killed. Most plants of Z. mauritiana resprouted vigorously within three months of the fire. Effects on the vegetative phenology of C. grandiflora persisted until 10 months after the fire, but by four months after the

8.04

Biological control: No biological controls have been introduced yet to Hawai'i.

http://www.hear.org/starr/hiplants/reports/html/cryptostegia_spp.htm

8.05