Tibouchina herbacea risk assessment

Pacific Island Ecosystems at Risk (PIER)

Tibouchina herbacea

RISK ASSESSMENT RESULTS: High risk, score: 24

Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment

	Tibouchina herbacea (cane ti, cane tibouchina, glorybush, tibouchina, tibouchinati ) Synonym: Arthrostemma herbacea DC. (basionym) Family - Melastomaceae	Answer	Score
1.01	Is the species highly domesticated? (If answer is 'no' then go to question 2.01)	n	0
1.02	Has the species become naturalized where grown?
1.03	Does the species have weedy races?
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”	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)	n	0
2.04	Native or naturalized in regions with tropical or subtropical climates	y	1
2.05	Does the species have a history of repeated introductions outside its natural range? y=-2	n
3.01	Naturalized beyond native range y = 1*multiplier (see Append 2), n= question 2.05	y	2
3.02	Garden/amenity/disturbance weed y = 1*multiplier (see Append 2)	y
3.03	Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2)	y	4
3.04	Environmental weed y = 2*multiplier (see Append 2)	y	4
3.05	Congeneric weed y = 1*multiplier (see Append 2)	y	2
4.01	Produces spines, thorns or burrs	n	0
4.02	Allelopathic	n	0
4.03	Parasitic	n	0
4.04	Unpalatable to grazing animals	y	1
4.05	Toxic to animals	n	0
4.06	Host for recognized pests and pathogens	n	0
4.07	Causes allergies or is otherwise toxic to humans	n	0
4.08	Creates a fire hazard in natural ecosystems	n	0
4.09	Is a shade tolerant plant at some stage of its life cycle	y	1
4.1	Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island)	y	1
4.11	Climbing or smothering growth habit	n	0
4.12	Forms dense thickets	y	1
5.01	Aquatic	n	0
5.02	Grass	n	0
5.03	Nitrogen fixing woody plant	n	0
5.04	Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers)	n	0
6.01	Evidence of substantial reproductive failure in native habitat	n	0
6.02	Produces viable seed.	y	1
6.03	Hybridizes naturally
6.04	Self-compatible or apomictic	y	1
6.05	Requires specialist pollinators	n	0
6.06	Reproduction by vegetative fragmentation	y	1
6.07	Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1	2	0
7.01	Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas)	y	1
7.02	Propagules dispersed intentionally by people	y	1
7.03	Propagules likely to disperse as a produce contaminant	n	-1
7.04	Propagules adapted to wind dispersal	n	-1
7.05	Propagules water dispersed	n	-1
7.06	Propagules bird dispersed	y	1
7.07	Propagules dispersed by other animals (externally)	n	-1
7.08	Propagules survive passage through the gut	y	1
8.01	Prolific seed production (>1000/m2)	y	1
8.02	Evidence that a persistent propagule bank is formed (>1 yr)	y	1
8.03	Well controlled by herbicides	n	1
8.04	Tolerates, or benefits from, mutilation, cultivation, or fire	y	1
8.05	Effective natural enemies present locally (e.g. introduced biocontrol agents)
	Total score:		24

Supporting data:

	Notes	Reference
1.01	No evidence
1.02
1.03
2.01	(1)"Native range: Southern Brazil, Uruguay and Paraguay ." (2)"Native: SOUTHERN AMERICA Brazil: Brazil Southern South America: Argentina; Paraguay; Uruguay"	(1)http://www.hear.org/pier/species/tibouchina_herbacea.htm (2)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl
2.02
2.03	(1)majority of the specimens collected from South American range were below 500 m except one from Bolivia at around 3300 m. (2)In Hawaii inhabits wet habitats above 1000 m on the Island of Hawaii - "Altitude at the study site ranges from 518 to 1232 m."	(1)http://mobot.mobot.org/cgi-bin/search_vast (2)Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
2.04	(1)"Native range: Southern Brazil, Uruguay and Paraguay ." (2)"Native: SOUTHERN AMERICA Brazil: Brazil Southern South America: Argentina; Paraguay; Uruguay"	(1)http://www.hear.org/pier/species/tibouchina_herbacea.htm (2)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl
2.05	"In Hawai‘i, "naturalized and locally abundant in disturbed mesic to wet forest." [No evidence of it being introduced elsewhere other than Hawaii].	http://www.hear.org/pier/species/tibouchina_herbacea.htm
3.01	"In Hawai‘i, "naturalized and locally abundant in disturbed mesic to wet forest."	http://www.hear.org/pier/species/tibouchina_herbacea.htm
3.02	"A non-native perennial sub-shrub, T. herbacea is invading both disturbed, open canopy sites and closed canopy wet native forests of Hawaii and Maui. … it appears to become established both in areas of high anthropogenic disturbance and natural areas." [This question not scored because it is scored for invasiveness under 3.04]	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
3.03	State Noxious Weed Lists for 46 States. State agriculture or natural resource departments.	http://plants.usda.gov/java/profile?symbol=TIHE2
3.04	"It forms dense monotypic stands over 3 m tall, clogging waterways and infesting wet, upland pastures and rainforest. … difficult to germinate because they require continuously moist conditions. Once established however the plant forms dense, monotypic thickets."	http://www.invasive.org/publications/xsymposium/proceed/08pg639.pdf
3.05	Tibouchina urvilleana - "Very invasive in Hawai‘i. On list of plants to be excluded from French Polynesia. Isolated specimens seen near the top of the cross-island road, Upolu, Samoa. One location on Rarotonga, Cook Islands."	http://www.hear.org/Pier/species/tibouchina_urvilleana.htm
4.01	No evidence of such structures.	http://www.hear.org/pier/species/tibouchina_herbacea.htm
4.02	No evidence
4.03	No evidence
4.04	"Cattle will not eat it."	http://www.invasive.org/publications/xsymposium/proceed/08pg639.pdf
4.05	No evidence
4.06	In the native range - "A number of insects attack the plant including Schrenkensteinia sp. (Lepidoptera: Schrenkensteinidae), Syphrea uberabensis (Col.: Chrysomelidae: Alticinae), Anthonomusopius and A. partiarius (Col.: Curculionidae: Sibinae), Lius sp. (Col.: Chrysomelidae:Alticinae). Studies with the Schrenkensteinia are the most advanced. It is a leaf-skele-tonizer that only attacks herbaceous Tibouchina species. It is, however, very susceptibleto Beauveria. It may not be suitable for biological control in Hawaii due to the presenceof several generalist lepidopteran parasitoids. There is also a large, undescribed geometridwhose larvae mimic the stems, either purple or green. It is a voracious defoliator." [No evidence that the above are economic pests].
4.07	No evidence
4.08	Probably not - herbaceaou species inhabits wet areas.	http://www.hear.org/pier/species/tibouchina_herbacea.htm AND http://www.invasive.org/publications/xsymposium/proceed/08pg639.pdf
4.09	(1)Plant in full sun for best color and maximum flowering. They can tolerate the shade but will not thrive. (2)"Plant invasion by Neotropical Melastomataceae is prominent in Hawaii. To understand life history traits of four successful invasive Melastomataceae, two shade-intolerant herbs (Arthrostema ciliatum and Tibouchina herbacea) and two shade-tolerant woody species (Clidemia hirta, a shrub, and Miconia calvescens, a tree) were subjected to three light levels and two watering regimes in a greenhouse. ..." "Our hypothesis was confirmed as the herbs from open habitats were most sensitive to light derpivation, whereas the seedlings of Miconia were better able to acclimate to low light." "The hight mortality of Tibouchina under LL indicates that this speceis may not be able to meet it metabolic requirements under deep shade, thereby restricting its habitat to open sites." (3)"A non-native perennial sub-shrub, T. herbacea is invading both disturbed,open canopy sites and closed canopy, wet native forests of Hawaii and Maui. This plant growns in dense stands in some open areas of West Maui and seems to be invading relatively intact native forests as well as disturbed sites," "The most important finding of the germination and seedling survival experiments was not the differences between habitats, but the fact that T. herbacea is capable of germinating, surviving and growing in relatively undisturbed, close canopy habitats." "Wester and Wood (1977) found that like C. hirta, T. herbacea, is shade tolerant, growing readily in moist, shaded forests in disturbed and undisturbed rainforests. ... Whether or not T> herbacea can ultimately generate dense stands in intact forests remains to be seen, but the life history similarities among these three noxious invaders and T. herbacea provide a warning that T. herbacea may become, if it is not already, a very successful forest invader." "My data support the idea that different life stages experience different spatio-temporal scales. Although T. herbacea produces fewer flowers and successfully pollinated capsules under canopy cover than in open, it is able to reproduce both sexually and vegetatively in both habitat types."	(1)http://en.wikipedia.org/wiki/Princess_flower (2)Baruch, Zdravko; Pattison, Robert R.; Goldstein, Guillermo. Responses to light and water availability of four invasive Melastomataceae in the Hawaiian islands International Journal of Plant Sciences 161 (1) : 107-118 Jan., 2000 (3)Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
4.1	Occurs on young lava flows (volcanic soils) on the Island of Hawaii.	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
4.11	No evidence.
4.12	(1)"It forms dense monotypic stands over 3 m tall, clogging waterways and infesting wet, upland pastures and rainforest. … difficult to germinate because they require continuously moist conditions. Once established however the plant forms dense, monotypic thickets." (2)"A non-native perennial sub-shrub, T. herbacea is invading both disturbed, open canopy sites and closed canopy, wet native forests of Hawaii and Maui. This plant grows in dense stands in some open areas of West Maui and seems to be invading relatively intact native forests as well as disturbed sites,"	(1)http://www.invasive.org/publications/xsymposium/proceed/08pg639.pdf (2)Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
5.01	"Herbs or subshrubs up to 1 m tall"	http://www.hear.org/pier/species/tibouchina_herbacea.htm
5.02
5.03
5.04
6.01	Flowering specimens collected from native range.	http://mobot.mobot.org/cgi-bin/search_vast
6.02	(1)Propagated by seed. (2)"T. herbacea is self-compatible, produces viable seeds …"	(1)http://www.hear.org/pier/species/tibouchina_herbacea.htm (2)Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
6.03	Don’t know - No evidence regarding hybridization in the genus Tibouchina - also the genus does not seem to be very well studied ecologically.	Chromosome Numbers and Their Systematic Significance in Some Mexican Melastomataceae Frank Almeda, Tsan Iang Chuang. Systematic Botany, Vol. 17, No. 4 (Oct. - Dec., 1992), pp. 583-593
6.04	"T. herbacea is self-compatible, produces viable seeds …"	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
6.05	Probably not - the specie is sold compatible with no evidence of specialist pollinators.	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
6.06	"With prolific vegetative and sexual reproduction it fits Bakers's description of a strong invader. … it spreads vegetatively and it appears to become established both in areas of height anthropogenic disturbance and natural areas." "T. herbacea is self-compatible, produces viable seeds, and reproduces vegetatively by growing roots along its leaf nodes, or by producing new shoots from rhizomes."	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
6.07	"In the Hawaiian Islands, T. herbacea grows to 4 m high and flowers after the first year."	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
7.01	"The location of T. herbacea along roadsides and some trails in the forest leaves little doubt that one method of seed dispersal is via human travel."
7.02	The species has ornamental value.
7.03	Probably not - no evidence that the species occurs or is grown in or around seed crops.
7.04	No evidence.
7.05	No evidence
7.06	"Like T. herbacea, M. calvenscens grows quickly, has a large range of conditions under which it may germinate, and produces many seeds. It also produces seed continuously, is dispersed widely by rodents and birds, has a large seed bank, and creates dense shade under which many native plants are unable to grow."
7.07	No evidence that the propagules have any means of attachment.
7.08	Probably yes - dispersed by birds.	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
8.01	(1)"Fruiting hypanthium 4-5 mm long, 3.5-5 mm wide. Seeds 0.25-0.5 mm long." (2)"It has the potential to be an especially noxious invader because its seeds are numerous and small …"	(1)http://www.hear.org/pier/species/tibouchina_herbacea.htm (2)Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
8.02	"Like T. herbacea, M. calvenscens grows quickly, has a large range of conditions under which it may germinate, and produces many seeds. It also produces seed continuously, is dispersed widely by rodents and birds, has a large seed bank, and creates dense shade under which many native plants are unable to grow."
8.03	Probably not - "However, manual and chemical controls are unlikely to be useful in either dense stands or where T. herbacea is spread across a wide area. Intact forests in Hawaii are often remotely located so accessing these populations may be difficult." [Logistic problems in herbiciding].
8.04	Probably yes - "Cutting T. herbacea individuals and leaving them on site would probably result in further spread due to its ability to vegetatively reproduce."	Kama N. Almasi. 2000. A Non-native Perennial Invades a Native Forest. Biological Invasions. 2(3): 219-230.
8.05	Some work has been undertaken on biological control in Hawai‘i.	(1)http://www.hear.org/pier/species/tibouchina_herbacea.htm (2)http://www.invasive.org/publications/xsymposium/proceed/08pg639.pdf

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This page created 26 December 2006