DC., Melastomataceae |
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Present on Pacific Islands? yes
Primarily a threat at high elevations? no
Risk assessment results: Hawaii/Pacific: High risk, score: 14 (Go to the risk assessment)
Risk assessment of Miconia calvescens from the Government of Queensland, Australia (PDF format)
Other Latin names: Merremia magnifica Triana
Common name(s): [more details]
English: bush currant, miconia, purple plague, velvetleaf |
Habit: tree
Description: An evergreen tree up to 15 m tall, with large, attractive leaves dark green above and purple beneath. The leaves have three distinctive veins running from the base to the tip of the leaf. Flowers are sweet-scented, short-lived, white to pink in color. Fruits are dark purple, sweet, and attractive to birds.
"Tree 4-8 (-16) m, the young branchlets, inflorescences, bracts (externally), and hypanthia moderately but rather deciduously stellate-puberulous; young branchlets quadrisulcate but terete with age, with a faint interpetiolar line at the nodes. Leaf blades oblong-elliptic, shortly blunt-acuminate at the apex, obtuse to rounded (occasionally cordulate) at the base, firm-membranaceous and obscurely undulate-serrulate, 17-30 (-40) cm long, 7-15 (-25) cm wide, 3-nerved (excluding the tenuous marginals) with the plane venules beneath laxly reticulate; petioles 3-6 cm long. Panicle 20-30 (-50) cm long and multiflorous, with paired primary branches; flowers 5-merous and sessile, the oblong bracteoles 2-3 mm long and caducous. Hypanthium 2-2.7 mm long; calyx tube 0.6-0.7 mm long, the broadly triangular interior lobes 0.1-0.3 mm long, the adnate external teeth not projecting. Petals white and glabrous on the surfaces but sometimes sparsely gland-edged, (2.3-) 2.8-3.1 mm long, (1-) 1.4-1.9 mm wide, oblong-obovate. Stamens slightly dimorphic; filaments (2.8-) 3.8-4.2 mm or (2.6-) 3.2-3.9 mm, glabrous or very sparsely glandular; thecae (2.2-) 3-3.1 mm or (1.9-) 2.6-2.8 mm long, oblong-subulate, 1-pored; connective not or slightly (to 0.4 mm) prolonged, bilobulate ventrally and tuberculate dorsally, usually beset with a few glands. Stigma slightly expanded; style glabrous or sparsely glandular, slightly immersed in the ovary apex; ovary 3-celled and 1/2-2/3 inferior, the apex granulose or sparsely glandular" (Wurdak, 1980).
"Branchlets, these often sulcate, inflorescences and sometimes the 5 leaf nerves beneath more or less mealy-pubescent with minute stellate trichomes; petioles 2-6 cm long; leaves somewhat undulate or repand-denticulate, ovate or oblong elliptic, acute or acuminate, rounded or subcordate at base, to narrowed (rarely), in age glabrous or nearly, sometimes 4 dm long; flowers mostly congested at the ends of the spreading-ascending panicle branchlets; calyx about 3 mm long, nearly entire; petals 2-3 mm long; connective minutely bilobed anteriorly; style 5-7 mm long, the stigma subpeltate" (Macbride, 1941; p. 393).
Miconia calvescens in Tahiti. Entire hillsides are
covered except for the larger trees that Miconia cannot overtop. When
these eventually die, a monospecific stand of Miconia will result. Photo of Miconia
calvescens in Tahiti by Jim Space.
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Habitat/ecology: "Forests and forest edges, grassland. In the native range, this plant is common in humid thickets and in riparian habitats from lowland to montane tropical forests. It is a fast growing, shade tolerant tree that completely transforms invaded communities into species-poor stands. The tree creates dense shade that eliminates almost all other species under its canopies. Invaded slopes are prone to landslides as the weak root system does not hold the soil well and the soil lacks a herbaceous ground cover" (Weber, 2003; p. 268).
Moist and wet forests from sea level to 5000 feet in Hawaii (1300 m in French Polynesia). Reproduces even in dense shade and eventually shades out all other plants except mature tall trees. "Miconia is considered by many natural area managers as Hawaii's most threatening weed. Brought to Hawaii from Central America in the late 1950s as an ornamental, this highly invasive tree rapidly naturalized and spread. Nearly all mesic and wet Hawaiian forests (>60 inches of rain per year) are potentially threatened if invasion is left unchecked. Miconia tolerates shade and and forms dense stands with heavy shade that replace native species, alter habitats, and may contribute to soil erosion. (Motooka et al., 2003). In New Caledonia, "importé comme plante ornementale de Tahiti où il est maintenant considéré comme un fléau. Encore rare sur le Territoire; devient localement envahissant mais pourra probablement être éliminé" (MacKee, 1994; p. 100).
Propagation: Seed, spread by wind, water and birds. Trees produce thousands of tiny bird-dispersed fruits at maturity. Most long-range spread is by frugivorous birds. Can be spread by seeds carried on shoes, equipment, etc. "A single mature plant can produce millions of seeds per year that are spread by birds or in soil on shoes, equipment, or the hooves of ungulates" (Motooka et al., 2003)
Native range: "Central and South America, where it occurs from about 18 degrees north to about 26 degrees south, and from lowlands to montane forests up to 1800 m in elevation" (Csurhes & Edwards, 1998; pp. 44-46).
Impacts and invaded habitats: "In 1937, Miconia calvescens, a large Andean tree, was introduced to French Polynesia. Since that time, it has significantly altered the forests of French Polynesia and other Pacific islands. Its large leaves (>1 m long) reduce the light interception by the seedlings of native forest species, and its shallow roots promote erosion and landslides. Each mature tree can produce millions of tiny seeds per year that are readily spread by birds, on construction equipment or on hiking boots. Particularly troublesome is the invader’s spread to mountainous crags up to 1300 m on Tahiti, a location in which eradication has been impossible. By the 1980s, M. calvescens dominated 70% of the forest habitats on Tahiti and had also invaded the neighbouring island of Moorea (Meyer &Florence 1996). It was reported in Hawaiian watersheds in the 1960s, but because management measures were not initiated until the 1990s, control of the plant now poses a formidable challenge (Shine et al. 2003b)." (Reaser et al., 2007, p. 102)
Presence:
Pacific | |||
Country/Terr./St. & Island group |
Location |
Cited status &
Cited as invasive & Cited as cultivated & Cited as aboriginal introduction? |
Reference &
Comments |
French Polynesia
Marquesas Islands |
Fatu Hiva Island |
introduced
invasive |
Lorence, David H./Wagner, Warren L. (2013) |
French Polynesia
Marquesas Islands |
Fatu Hiva Island |
introduced
invasive |
Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2013)
Voucher cited: D.H. Lorence, L. Dunn, S.P. Perlman, K.R. Wood & J.-Y. Meyer 9027 (PAP) Naturalisée, menace pour la biodiversité. |
French Polynesia
Marquesas Islands |
Fatu Hiva Island |
National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2003) (voucher ID: PTBG 39293)
Taxon name on voucher: Miconia calvescens |
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French Polynesia
Marquesas Islands |
Nuku Hiva (Nukahiva) Island |
introduced
invasive |
Lorence, David H./Wagner, Warren L. (2013) |
French Polynesia
Marquesas Islands |
Nuku Hiva (Nukahiva) Island |
introduced
invasive |
Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2013)
Voucher cited: K.R. Wood, J.-Y. Meyer, J.-P. Luce & W. Tetuanui 6334 (PAP) Naturalisée, menace pour la biodiversité. |
French Polynesia
Marquesas Islands |
Nuku Hiva (Nukahiva) Island |
National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1997) (voucher ID: PTBG 27727)
Taxon name on voucher: Miconia calvescens DC. |
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French Polynesia
Society Islands |
Moorea Island |
introduced
invasive |
Welsh, S. L. (1998) (p. 182)
Voucher cited: Florence 7818 |
French Polynesia
Society Islands |
Moorea Island |
introduced
invasive |
Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2013)
Vouchers cited: J. Florence 7818 (PAP), P. Birnbaum 77 (PAP) Naturalisée, menace pour la biodiversité. |
French Polynesia
Society Islands |
Moorea Island |
Bishop Museum (Honolulu) (1986) (voucher ID: BISH 544426)
Taxon name on voucher: Miconia calvescens DC. |
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French Polynesia
Society Islands |
Raiatea (Havai) Island | Fosberg, F. R. (1997) (p. 76) | |
French Polynesia
Society Islands |
Raiatea (Havai) Island |
introduced
invasive |
Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2013)
Voucher cited: J. Florence & P. Birnbaum 9945 (PAP) Naturalisée, Menace pour la biodiversité |
French Polynesia
Society Islands |
Tahiti Island |
introduced
invasive |
Welsh, S. L. (1998) (p. 182)
Vouchers cited: BRY 25764, Fosberg & Stone 61311 |
French Polynesia
Society Islands |
Tahiti Island |
introduced
invasive |
Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2013)
Vouchers cited: J. Florence 2645 (PAP), J. Florence 5043 (PAP), J. Florence 8773 (PAP), P. Birnbaum 78 (PAP) Naturalisée. Menace pour la biodiversité. |
French Polynesia
Society Islands |
Tahiti Island |
Bishop Museum (Honolulu) (1982) (voucher ID: BISH 493267)
Taxon name on voucher: Miconia calvescens DC. |
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French Polynesia
Society Islands |
Tahiti Island |
Bishop Museum (Honolulu) (1988) (voucher ID: BISH 583633)
Taxon name on voucher: Miconia calvescens DC. |
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French Polynesia
Society Islands |
Tahiti Island |
Bishop Museum (Honolulu) (1988) (voucher ID: BISH 583634)
Taxon name on voucher: Miconia calvescens DC. |
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French Polynesia
Society Islands |
Tahiti Island |
Bishop Museum (Honolulu) (1988) (voucher ID: BISH 583635)
Taxon name on voucher: Miconia calvescens DC. |
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French Polynesia
Society Islands |
Tahiti Island |
Bishop Museum (Honolulu) (1988) (voucher ID: BISH 583636)
Taxon name on voucher: Miconia calvescens DC. |
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French Polynesia
Society Islands |
Tahiti Island |
National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1981) (voucher ID: PTBG 37701)
Taxon name on voucher: Miconia calvescens DC. |
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State of Hawaii
Hawaiian Islands |
Hawaii (Big) Island |
introduced
invasive cultivated |
Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 903, 1884) |
State of Hawaii
Hawaiian Islands |
Kauai Island |
introduced
invasive cultivated |
Conant, Patrick (1996) (pp. 1-2)
Voucher cited: A. Bell sub D. Lawrence 7715 (BISH, PTBG) |
State of Hawaii
Hawaiian Islands |
Maui Island |
introduced
invasive cultivated |
Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 903, 1884)
East Maui |
State of Hawaii
Hawaiian Islands |
Oahu Island |
introduced
invasive cultivated |
Conant, Patrick (1996) (pp. 1-2)
Vouchers cited: P. Conant s.n. (BISH, 2 specimens) |
New Caledonia
New Caledonia |
New Caledonia Islands |
introduced
|
Meyer, Jean-Yves (2000) (p. 100)
"Potential invader". |
New Caledonia
New Caledonia |
New Caledonia Islands |
introduced
invasive cultivated |
Gargominy, Oliver/Bouchet, Philipe/Pascal, Michel/Jaffre, Tanguy/Tourneu, Jean-Christophe (1996) (p. 382)
Only one location. Importé de Tahiti où il est maintenant considéré comme un fléau. Encore rare sur le Territoire; une seule localité. |
New Caledonia
New Caledonia Archipelago |
Île Grande Terre |
introduced
invasive cultivated |
MacKee, H. S. (1994) (p. 100)
Voucher cited: Baudin 356 (NOU) |
Pacific Rim | |||
Country/Terr./St. & Island group |
Location |
Cited status &
Cited as invasive & Cited as cultivated & Cited as aboriginal introduction? |
Reference &
Comments |
Australia
Australia (continental) |
Queensland |
introduced
invasive |
Csurhes, S./Edwards, R. (1998) (p. 44)
Subject of an eradication program. |
Central America
Central America (Pacific rim) |
Guatemala (Republic of) |
native
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U.S. Dept. Agr., Agr. Res. Serv. (2013) |
Central America
Central America (Pacific rim) |
Nicaragua (Republic of) |
native
|
U.S. Dept. Agr., Agr. Res. Serv. (2013) |
Central America
Central America (Pacific rim) |
Panama (Republic of) |
native
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U.S. Dept. Agr., Agr. Res. Serv. (2013) |
Mexico
Mexico |
Mexico (United Mexican States) |
native
|
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Chiapas |
Singapore
Singapore |
Singapore (Republic of) |
introduced
cultivated |
Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. (2009) (p. 61)
Cultivated only |
South America (Pacific rim)
South America (Pacific rim) |
Colombia |
native
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U.S. Dept. Agr., Agr. Res. Serv. (2013) |
South America (Pacific rim)
South America (Pacific rim) |
Ecuador (Republic of) (continental) |
native
|
U.S. Dept. Agr., Agr. Res. Serv. (2013) |
South America (Pacific rim)
South America (Pacific rim) |
Perú (Republic of) |
native
|
U.S. Dept. Agr., Agr. Res. Serv. (2013) |
Comments: On the State of Hawaii noxious weed list.
It has become established in northern Queensland, Australia, where an eradication effort is beginning (Csurhes & Edwards, 1998; pp. 44-46).
Miconia is the greatest invasive species problem in French Polynesia. It has become established in Hawaii, where it shows every indication of being just as bad. It is presently subject of an eradication effort in Hawaii. Other oceanic islands should be vigilant to keep this very dangerous pest out or to immediately eradicate it if discovered.
Reported to be naturalized in Jamaica and Sri Lanka (Csurhes & Edwards, 1998; pp. 44-46).
Subject of an eradication program in New Caledonia (Meyer & Jourdan, 2005).
Control:
Physical: "Smaller saplings are easy to grub out by hand" (Motooka et al., 2003).
Chemical: "Sensitive to triclopyr ester in foliar applications (E. Tamura, HDOA), to cut surfaces and as basal bark treatments, and also to glyphosate applied to cut surfaces. Thin line application of undiluted triclopyr ester effective"
Biological: "Biocontrol agents from Latin America are being evaluated for control of velvet tree. A fungus (Colletotrichum gloesporioides f. sp. miconiae) has been established on Hawaii and Maui, where it has caused leaf spotting and early leaf drop (Pat Conant, HDOA)" (Motooka et al., 2003).
"Biological control of miconia (Miconia calvescens) became a management option as the severity of its threat to Hawaiian ecosystems was recognized. No weed in Hawaii has received as much publicity, attention, and funding for control. Three fungal pathogens have been considered as potential agents. Colletotrichum gloesoporioides f. sp. miconiae was assessed within six months, the petition for release approved within eight months and the fungus released on the islands of Hawaii and Maui in 1997. It is established on Hawaii and has spread to other areas. Its effectiveness is under evaluation. Pseudocercospora tamonae causes extensive damage to leaves, attacks other melastomes and the seedlings of some Myrtaceae but only fruits on miconia. It is very uncertain whether this species will be approved for release. Coccodiella myconae produces large wart-like growths that deform leaves considerably. It appears to be an obligate parasite of miconia but hyperparasitized by another species tentatively identified as Sagenomella alba. It has proven difficult to transfer from one plant to another where it does not sporulate (Smith et al., 2002; p. 45).
Other potential fungal control agents include "a tar spot disease, Guignardia sp. (Dothideales. Mycosphaerellaceae), and a leaf blight, Kuronomyces sp. (Mycelia sterilis, ?Basidiomycetes)" (Smith et al., 2002; p. 96).