Pacific Island Ecosystems at Risk (PIER)


Vitex trifolia


RISK ASSESSMENT RESULTS: High risk, score: 9 (native to the Pacific region, excluding Hawai‘i)


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

Vitex trifolia L. Family - Verbenaceae (currently Lamiaceae). Common Names(s) - Blue vitex, Indian privet. Synonym(s) - NA.

Answer

Score

1.01

Is the species highly domesticated?

y=-3, n=0

n

0

1.02

Has the species become naturalized where grown?

y=1, n=-1

1.03

Does the species have weedy races?

y= 1, n=-1

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

1

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

1

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

2

3.02

Garden/amenity/disturbance weed y = 1*multiplier (see Append 2)

n=0

y

2

3.03

Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2)

n=0

3.04

Environmental weed y = 2*multiplier (see Append 2)

n=0

n

0

3.05

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

n=0

y

2

4.01

Produces spines, thorns or burrs

y=1, n=0

n

0

4.02

Allelopathic

y=1, n=0

n

0

4.03

Parasitic

y=1, n=0

n

0

4.04

Unpalatable to grazing animals

y=1, n=-1

n

-1

4.05

Toxic to animals

y=1, n=0

n

0

4.06

Host for recognized pests and pathogens

y=1, n=0

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

n

0

4.09

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

y=1, n=0

n

0

4.10

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

y=1, n=0

y

1

4.11

Climbing or smothering growth habit

y=1, n=0

n

0

4.12

Forms dense thickets

y=1, n=0

y

1

5.01

Aquatic

y=5, n=0

n

0

5.02

Grass

y=1, n=0

n

0

5.03

Nitrogen fixing woody plant

y=1, n=0

n

0

5.04

Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers)

y=1, n=0

n

0

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

0

6.02

Produces viable seed.

y=1, n=-1

y

1

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

y

1

6.05

Requires specialist pollinators

y=-1, n=0

n

0

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

y

1

6.07

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

See left

2

0

7.01

Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas)

y=1, n=-1

n

-1

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

1

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

n

-1

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

-1

7.05

Propagules water dispersed

y=1, n=-1

7.06

Propagules bird dispersed

y=1, n=-1

y

1

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

n

-1

7.08

Propagules survive passage through the gut

y=1, n=-1

y

1

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

n

-1

8.02

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

y=1, n=-1

8.03

Well controlled by herbicides

y=-1, n=1

y

-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:

9

Supporting data:

Notes

Source

1.01

(1)No evidence of extensive domestication

(1)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

1.02

1.03

2.01

(1)Blue Vitex is native to the broad area from eastern South Africa to Asia, Australia and the Pacific.

(1)Rauch, F. D., and P. R. Weissich. 2009. Small Trees for the Tropical Landscape. University of Hawaii Press, Honolulu

2.02

(1)Blue Vitex is native to the broad area from eastern South Africa to Asia, Australia and the Pacific.

(1)Rauch, F. D., and P. R. Weissich. 2009. Small Trees for the Tropical Landscape. University of Hawaii Press, Honolulu

2.03

(1)Zone(s): 9-11 (2)at 0 – 150 (– 1500) m altitude. In humid areas the species is usually common at low altitudes, becoming rarer higher up. In dryer areas the species can also be more common at high evaluation. [broad potential elevational range]

(1)Jarrett, A. 2003. Ornamental Tropical Shrubs. Pineapple Press Inc. (2)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

2.04

(1)Blue Vitex is native to the broad area from eastern South Africa to Asia, Australia and the Pacific.

(1)Rauch, F. D., and P. R. Weissich. 2009. Small Trees for the Tropical Landscape. University of Hawaii Press, Honolulu

2.05

(1)Because of its local use as an ornamental and a medicinal plant, it is also widely cultivated in and outside its natural area. (2)Locations: Koko Crater Botanical Garden Waimea Arboretum & Botanical Garden

(1)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40 (2)Imada, C. T., G. W. Staples, and D. R. Herbst. 2005. Annotated Checklist of Cultivated Plants of Hawai‘i. http://www2.bishopmuseum.org/HBS/botany/cultivatedplants/ [Accessed 07 May 2010]

3.01

(1)Vitex trifolia L. and var. variegata Moldenke. INDIAN PRIVET; INDIAN WILD PEPPER. Asia; East Indies; Australia. Naturalized in disturbed sites in South Florida; "especially near coast" (2)naturalized elsewhere (3)Vitex trifolia L. New naturalized record Native from Madagascar and eastern South Africa throughout Asia, New Guinea, northern Australia, and the Pacific, V. trifolia is commonly cultivated in Hawai‘i and often used as a windbreak (Staples & Herbst 2005). In Kalaupapa it is known from 2 naturalized populations; one behind the old rock quarry and the other just past the turnoff to Kauhakö Crater on Damien road. Material examined. MOLOKA‘I: Kalaupapa peninsula, at back of old rock quarry in mixed, open, nonnative scrub, 2 patches containing several plants each, up to 3 m tall, 15 m, 12 Oct 2005, Wysong 804.

(1)Morton, J. F. 1976. Pestiferous spread of many ornamental and fruit species in south Florida. Proc. Fla. State Hort. Soc 89:348-353. (2)USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN) [Online Database]. National Germplasm Resources Laboratory, Beltsville, Maryland. URL: http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl [Accessed 07 May 2010] (3)Wysong, M. and G. Hughes. 2007. New Hawaiian plant records for the Island of Moloka‘i. Bishop Museum Occasional Papers 96: 1-8.

3.02

(1)Vitex trifolia. Listed as a FLEPPC CATEGORY II plant. Invasive exotics that have increased in abundance or frequency but have not yet altered Florida plant communities to the extent shown by Category I species. These species may become ranked Category I, if ecological damage is demonstrated.

(1)FLEPPC. 2009. List of Invasive Plant Species – Fall 2009 – Wildland Weeds 12(4): 13-16.

3.03

(1)Vitex or Dralakaka (Vitex trifolia) is an aggressive shrub in pastures in New Caledonia and Fiji...V. trifolia is an indigenous shrubby species considered as an invasive species for the pasture through all the main island. [no impacts listed for this indigenous weed, but sufficient evidence to answer yes to question 3.02]

(1)Blanfort, V., and W. Orapa. 2003. Ecology, Impacts and Management of Invasive Plant Species in Pastoral Areas. in Proceedings of the Regional Workshop on Invasive Plant Species in Pastoral Areas. Koné, New Caledonia

3.04

(1)Vitex trifolia. Listed as a FLEPPC CATEGORY II plant. Invasive exotics that have increased in abundance or frequency but have not yet altered Florida plant communities to the extent shown by Category I species. These species may become ranked Category I, if ecological damage is demonstrated. [not evidence of serious environmental impacts yet]

(1)FLEPPC. 2009. List of Invasive Plant Species – Fall 2009 – Wildland Weeds 12(4): 13-16.

3.05

(1)Beach vitex (Vitex rotundifolia) is a salt tolerant, perennial, invasive shrub that has naturalized in coastal areas of the southeastern United States. Since its introduction in the 1980's, this Pacific Rim native has invaded many fragile beach dune ecosystems along the Mid-Atlantic, Southern Atlantic, and Gulf of Mexico. Large-scale monocultures of beach vitex supplant native species through rapid vegetative reproduction and seed production. Fruits are capable of water-based dispersal, allowing for potential rapid range expansion in coastal areas. Ecosystem damage resulting from exclusion of native plant species by beach vitex and fears associated with potential negative impacts on sea turtle nesting have served to promote the control and survey efforts presently underway in coastal areas of the Carolinas, Virginia, and Maryland. (2)Vitex rotundifolia is considered an invasive species in the Carolinas and has the potential to spread to many more coastal communities along the shores of the United States (Madsen,et al, 2005). Beach vitex is a rapidly growing and sprawling shrub both vertically and horizontally that is very tolerant of salt and drought (Gresham & Neal, undated). Beach vitex produces a large seed bank and can reproduce vegetatively through rooting at leaf nodes along runners (Gresham & Neal, undated). The impact of its aggressive growth pattern leads to little light reaching the soil surface where it dominates as monocultures preventing native species from establishing (Gresham & Neal, undated). In addition it has been suggested from scientific observations that the plant releases some allelopathic compounds that have actions in the soil to make it hydrophobic, causing drought stress to less tolerant native species (Gresham & Neal, undated). The structure of the plant's root system does not make it an ideal dune stabiliser compared to fibrous root systems of native species causing higher rates of dune erosion (SCNPS, undated). It causes mortality in young sea turtles by entangling them in its long runners and impacts nesting sites for reproductive females (SCNPS, undated) (please see impact information in the North and South Carolina distribution records). Beach vitex also impacts multi-million dollar beach renourishment projects (Madsen,et al, 2005).

(1)Whitwell, T., M. Cousins, J. Briggs, T. Whitwell, C. Gresham, and J. Whetstone. 2010. Beach Vitex (Vitex rotundifolia): An Invasive Coastal Species. Invasive Plant Science and Management:0000-0000 (2)Global Invasive Species Database (http://www.issg.org/database) [Accessed 10 May 2010]

4.01

(1)Vitex trifolia is a shrub up to 6 m tall, leaflets (1-)3, glabrous above (except for the midrib), densely greyish puberulous below. Median leaflet oblong-elliptical to obovate, 2.5-9.5 cm x 1.5-4 cm, with 6- 13 pairs of lateral veins, on a 1-6 mm long petiolule, lateral leaflets sessile or subsessile. [no spines, thorns or burrs]

(1)Orwa C, Mutua A , Kindt R , Jamnadass R, Simons A. 2009. Agroforestree Database:a tree reference and selection guide

version 4.0 (http://www.worldagroforestry.org/af/treedb/)

4.02

(1)The row spacing of the saplings is about 0.6 -- 0.8 m. In some areas the cuttings of lianas such as Vitex trifolia , Ipomoea pes-caprae and Canavalia maritima are planted in the network of Pandanus tectorius . The space between two rows is about 0.5 m. The practice indicates that Pandanus tectorius can survive in stretch on the active sand land, which is conducive to protecting the saplings of Casuarina equisetifolia . The survival rate is higher in the parallel lines than that in the vertical lines to the chief wind direction. In addition , fewer plants of Casuarina equisetifolia and Pandanus tectorius wilted on the land covered by natural lianas (e. g. Vitex trifolia) . Dense plants of Vitex trifolia can preserve humidity , adjust temperature and favor tree growth. The root systems of Vitex trifolia and trees are growing in the different soil layers so that there is no competition for water and nutrients. [a nurse plant with no apparent evidence of allelopathy]

(1)Hua, B., and L. Qiang. 2001. Desertification and re-afforestation of the coastal land in Changjiang County, Hainan Island. Chinese Journal of Geochemistry 20:374-382

4.03

(1)Not parasitic

(1)Orwa C, Mutua A , Kindt R , Jamnadass R, Simons A. 2009. Agroforestree Database:a tree reference and selection guide

version 4.0 (http://www.worldagroforestry.org/af/treedb/)

4.04

(1)Table 1 Food items found in rumen samples from rusa deer (n = 61) from Mépouiri (sclerophyll forest/savanna vegetation). Status (MacKee 1994; Jaffré et al. 2001): N = native species; I = introduced naturalised species; – = status unknown. [List includes Vitex trifolia]

(1)de Garine-Wichatitsky, M., Y. Soubeyran, D. Maillard, and P. Duncan. 2005. The diets of introduced rusa deer (Cervus timorensis russa) in a native sclerophyll forest and a native rainforest of New Caledonia. New Zealand Journal of Zoology 32:117-126

4.05

(1)Poison: Oils from the leaves of V. trifolia show considerable mosquito repellent activity. The active principle in the leaves of V. trifolia has been identified as rotundinal, a cycloterpene aldehyde. V. trifolia shows considerable potential as a botanical pesticide that may be applied both indoors and outdoors. (2)Table 1 Food items found in rumen samples from rusa deer (n = 61) from Mépouiri (sclerophyll forest/savanna vegetation). Status (MacKee 1994; Jaffré et al. 2001): N = native species; I = introduced naturalised species; – = status unknown.[List includes Vitex trifolia...Apparently toxic to invertebrates in concentration, but no evidence of acute toxicty to vertebrates]

(1)Orwa C, Mutua A , Kindt R , Jamnadass R, Simons A. 2009. Agroforestree Database:a tree reference and selection guide

version 4.0 (http://www.worldagroforestry.org/af/treedb/) (2)de Garine-Wichatitsky, M., Y. Soubeyran, D. Maillard, and P. Duncan. 2005. The diets of introduced rusa deer (Cervus timorensis russa) in a native sclerophyll forest and a native rainforest of New Caledonia. New Zealand Journal of Zoology 32:117-126

4.06

(1)Problems: mushroom root rot, scale insects (2)Pests recorded Insects: Hyblaea puera (teak defoliator) Nematodes: Helicotylenchus dihystera (common spiral nematode) Pests recorded at the generic level (Vitex): Insects: Coccus hesperidum (brown soft scale) Diaspidiotus perniciosus (San José scale) Parabemisia myricae (bayberry whitefly) Rastrococcus iceryoides (mango mealy bug)

(1)Jarrett, A. 2003. Ornamental Tropical Shrubs. Pineapple Press Inc. (2)CAB International, 2005. Forestry Compendium. Wallingford, UK: CAB International.

4.07

(1)Boundary or barrier or support: V. trifolia is often used as a hedge plant, although it may trigger various allergic reactions (sneezing, respiratory problems, dizziness, headache, nausea) to people trimming or pruning such hedges. (2)That respiratory irritants are not limited to floral parts, is further evidenced by the hayfever-like reactions experienced by some Florida residents when a hedge of Vitex trifolia L. (20) or even the popular Surinam cherry (Eugerda uniflora L.) is trimmed;

(1)Orwa C, Mutua A , Kindt R , Jamnadass R, Simons A. 2009. Agroforestree Database:a tree reference and selection guide

version 4.0 (http://www.worldagroforestry.org/af/treedb/) (2)Morton, J. F. 1969. Some Ornamental Plants Excreting Respiratory Irritants. Florida State Horticultural Society:415-421

4.08

(1)ECOLOGY. Beaches, inland edge of mangrove swamps, grasslands, (littoral) forest and in secondary vegetation, often near water. [no evidence of increased fire hazards or high flammability]

(1)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

4.09

(1)Exposure: Full sun or filtered shade in the hottest deserts; full sun elsewhere.

(1)Irish, M. 2008. Trees and Shrubs for the Southwest: Woody Plants for Arid Gardens. Timber Press, Portland

4.10

(1)Soil: tolerant of most soils but prefers well-drained, moist soils. (2)Soil: sands or more rarely in clay, often over limestone, coral, volcanic soils or shale

(1)Jarrett, A. 2003. Ornamental Tropical Shrubs. Pineapple Press Inc. (2)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

4.11

(1)Vitex will reach a height of 10 to 12 feet and quickly becomes tree-like if neglected or trained to encourage multi-trunk development. However, this plant creates a nice, dense shrub if it is properly pruned and will be nearly prostrate if planted on a sandy beach.

(1)Gilman, E. F. 1999. Vitex trifolia ‘Variegata’. Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Retrieved from http://hort.ufl.edu/shrubs/VITTRIB.PDF

4.12

(1)Often a solitary tree but sometimes occurring in tickets.

(1)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

5.01

(1)Distribution: Throughout India, mainly along the water courses (2)ECOLOGY. Beaches, inland edge of mangrove swamps, grasslands, (littoral) forest and in secondary vegetation, often near water.

(1)Warrier, P. K., and V. P. K. Nambiar. 1993. Indian medicinal plants: a compendium of 500 species. Orient Longman (2)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

5.02

(1)Lamiaceae [formerly Verbenaceae]

(1)USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN) [Online Database]. National Germplasm Resources Laboratory, Beltsville, Maryland. URL: http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl [Accessed 07 May 2010]

5.03

(1)Lamiaceae [formerly Verbenaceae]

(1)USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN) [Online Database]. National Germplasm Resources Laboratory, Beltsville, Maryland. URL: http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl [Accessed 07 May 2010]

5.04

(1)Not a geophyte

(1)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

6.01

(1)No evidence of substantial reproductive failure in native habitat

(1)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

6.02

(1)A preliminary study of the reproductive and spatial strategy of the two species show that V.trifolia uses a vegetative reproductive strategy even when producing numerous of seeds but very few seedlings could be observed (seeds could be in dormancy waiting a right period to germinate)

(1)Blanfort, V., and W. Orapa. 2003. Ecology, Impacts and Management of Invasive Plant Species in Pastoral Areas. in Proceedings of the Regional Workshop on Invasive Plant Species in Pastoral Areas. Koné, New Caledonia

6.03

Unknown

6.04

(1)Self-compatibility appears to be a constant feature of breeding systems in the Verbenaceae [family characteristic]

(1)Kadereit, J. W. 2004. Flowering plants, dicotyledons: Lamiales (except Acanthaceae including Avicenniaceae). Springer Verlag

6.05

(1)"…the main pollinators are insects with long tongues, probing for the nectar at the bottom of the tube…Other pollinators appear to be Hymenoptera and Diptera…The majority of pollination appears to be effected by small nectar-seeking bees" [family description, but Vitex floral morphology does not suggest a specialized pollinator]

(1)Kadereit, J. W. 2004. Flowering plants, dicotyledons: Lamiales (except Acanthaceae including Avicenniaceae). Springer Verlag

6.06

(1)A preliminary study of the reproductive and spatial strategy of the two species show that V.trifolia uses a vegetative reproductive strategy even when producing numerous of seeds but very few seedlings could be observed (seeds could be in dormancy waiting a right period to germinate)

(1)Blanfort, V., and W. Orapa. 2003. Ecology, Impacts and Management of Invasive Plant Species in Pastoral Areas. in Proceedings of the Regional Workshop on Invasive Plant Species in Pastoral Areas. Koné, New Caledonia

6.07

(1)Vitex will reach a height of 10 to 12 feet and quickly becomes tree-like if neglected or trained to encourage multi-trunk development. However, this plant creates a nice, dense shrub if it is properly pruned and will be nearly prostrate if planted on a sandy beach...Growth rate: fast [probably a minimum of 2 to 3 years, if not less]

(1)Gilman, E. F. 1999. Vitex trifolia ‘Variegata’. Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Retrieved from http://hort.ufl.edu/shrubs/VITTRIB.PDF

7.01

(1)Fruit a fleshy, subglobose drupe 5-7 mm in diameter, black at maturity, 4-seeded [no evidence, and fruits/seeds with no means of external attachment]

(1)Whistler, W. A. 1992. Flowers of the Pacific island seashore: a guide to the littoral plants of Hawai'i, Tahiti, Samoa, Tonga, Cook Islands, Fiji and Micronesia. Isle Botanica, Honolulu, Hawaii

7.02

(1)Popular ornamental (2)A number of species (in particular Vitex trifolia L. and V. negundo L.) are extensively used and grown for both medicinal use and for ornamentation.

(1)Rauch, F. D., and P. R. Weissich. 2009. Small Trees for the Tropical Landscape. University of Hawaii Press, Honolulu (2)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

7.03

(1)Fruit a fleshy, subglobose drupe 5-7 mm in diameter, black at maturity, 4-seeded [no evidence, and fruits/seeds relatively large and unlikely to contaminate produce]

(1)Whistler, W. A. 1992. Flowers of the Pacific island seashore: a guide to the littoral plants of Hawai'i, Tahiti, Samoa, Tonga, Cook Islands, Fiji and Micronesia. Isle Botanica, Honolulu, Hawaii

7.04

(1)fruits globose drupes, purplish black when ripe.

(1)Warrier, P. K., and V. P. K. Nambiar. 1993. Indian medicinal plants: a compendium of 500 species. Orient Longman

7.05

(1)Distribution: Throughout India, mainly along the water courses [suggests water dispersal] (2)ECOLOGY. Beaches, inland edge of mangrove swamps, grasslands, (littoral) forest and in secondary vegetation, often near water.

(1)Warrier, P. K., and V. P. K. Nambiar. 1993. Indian medicinal plants: a compendium of 500 species. Orient Longman (2)de Kok, R. 2008. The genus Vitex (Labiatae) in the Flora Malesiana region, excluding New Guinea. Kew Bulletin 63:17-40

7.06

(1)fruits globose drupes, purplish black when ripe. (2)Animal dispersal is frequent in the family...Those with a fleshy pericarp, such as species of Vitex (Viticoideae)…are probably often distributed by birds.

(1)Warrier, P. K., and V. P. K. Nambiar. 1993. Indian medicinal plants: a compendium of 500 species. Orient Longman (2)Kadereit, J. W. 2004. Flowering plants, dicotyledons: Lamiales (except Acanthaceae including Avicenniaceae). Springer Verlag

7.07

(1)Fruit a fleshy, subglobose drupe 5-7 mm in diameter, black at maturity, 4-seeded [no evidence, and fruits/seeds with no means of external attachment]

(1)Whistler, W. A. 1992. Flowers of the Pacific island seashore: a guide to the littoral plants of Hawai'i, Tahiti, Samoa, Tonga, Cook Islands, Fiji and Micronesia. Isle Botanica, Honolulu, Hawaii

7.08

(1)fruits globose drupes, purplish black when ripe. (2)Animal dispersal is frequent in the family...Those with a fleshy pericarp, such as species of Vitex (Viticoideae)…are probably often distributed by birds.

(1)Warrier, P. K., and V. P. K. Nambiar. 1993. Indian medicinal plants: a compendium of 500 species. Orient Longman (2)Kadereit, J. W. 2004. Flowering plants, dicotyledons: Lamiales (except Acanthaceae including Avicenniaceae). Springer Verlag

8.01

(1)Fruit a fleshy, subglobose drupe 5-7 mm in diameter, black at maturity, 4-seeded [unlikely with such relatively large fruits & seeds]

(1)Whistler, W. A. 1992. Flowers of the Pacific island seashore: a guide to the littoral plants of Hawai'i, Tahiti, Samoa, Tonga, Cook Islands, Fiji and Micronesia. Isle Botanica, Honolulu, Hawaii

8.02

Unknown

8.03

(1)Beach vitex [Vitex rotundifolia (L.f.)] is a perennial woody shrub native to Hawaii and countries of the Pacific Rim. Beach vitex thrives on coastal sand dunes and was introduced into the southeastern United States for use as an ornamental and dune stabilizing plant. Today, however, it is considered a noxious weed and invasive species due to its aggressive spread and competition with native flora and fauna. Field and greenhouse studies were conducted from 2006 through 2008 to evaluate the efficacy of selected herbicides and mixtures on beach vitex. In one experiment, beach vitex control at 1 month after treatment (MAT) was greatest with glyphosate and glyphosate plus imazapyr (73% to 84%) and at 12 MAT, control increased to 90 and 94%, respectively. Control with triclopyr mixtures was less than 36% at 1 MAT and less than 11% at 12 MAT. In a second experiment, at 1 MAT glyphosate, imazapyr, and metsulfuron controlled beach vitex 66 to 82%. Control with aminopyralid, imazamox, and penoxsulam was less than 50%. At 8 MAT greatest control was observed with glyphosate and imazapyr (83 and 90%, respectively). Control levels with other treatments were significantly lower at 19 to 52%. In a greenhouse study at 3 weeks after treatment (WAT), control was 37 to 68% with glyphosate and 41 to 76% with imazapyr. At 5 WAT, control was 34 to 87% with glyphosate and 48 to 95% with imazapyr. Dry weight was 4.47 to 5.00 g in glyphosate treatments and 3.50 to 6.18 in imazapyr treatments as compared to the nontreated dry weight of 6.93 g. The absorption and translocation of glyphosate in beach vitex was evaluated with cut stem and foliar applications. Plants were treated with a prepared 14C-glyphosate solution and harvested at 6, 24, 48, 92, and 196 hours after treatment (HAT). In beach vitex cut stems, time of harvest was not significant indicating that all absorption and translocation occurred within the first six hours after treatment. The greatest amount of herbicide recovered remained in the stump (348,408 DPM). A moderate amount translocated to the first root section (14,572 DPM) and a minimal amount translocated to root segments greater distances from the stump (1,657 and 617 DPM for second 10 cm of roots and end roots, respectively). In foliar treatments, the greatest recovered herbicide remained in the treated leaf at 17,828 DPM. Recovered 14C-glyphosate in other plant parts did not differ and ranged 1,222 to 4,300 DPM. At 6 and 24 HAT, 2,081 to 2,825 DPM were recovered. Greater amounts of 6,432 to 9,661 were recovered at 48 to 196 HAT. Translocation of the applied herbicide was generally low with both application methods. [control for Vitex rotundifolia would likely be effective against V. trifolia]

(1)True, S. L. 2009. The Biology and Control of Beach Vitex (Vitex rotundifolia) and Common Reed (Phragmites australis). MSc. Thesis. North Carolina State University.

8.04

Unknown

8.05

Unknown


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


[ Return to PIER homepage ] [Risk assessment page]


This page created 24 October 2010