Tabebuia heterophylla
(pink trumpet tree)

Pictures

Picture	Title	Caption	Copyright
Title Flowers and foliage Caption Tabebuia heterophylla; flowers and foliage. Copyright ©A.R. Pittaway	Flowers and foliage	Tabebuia heterophylla; flowers and foliage.	©A.R. Pittaway

Identity

Preferred Scientific Name

• Tabebuia heterophylla (DC.) Britton, 1915

Preferred Common Name

• pink trumpet tree

Other Scientific Names

• Bignonia leucoxylon L., 1753
• Bignonia pentaphylla L., 1763
• Leucoxylon riparia Raf., 1838
• Raputia heterophylla DC., 1822
• Tabebuia pallida auct. non (L.) Hemsley
• Tabebuia pentaphylla (L.) Hemsl., 1882
• Tabebuia riparia (Raf.) Sandwith, 1955
• Tabebuia triphylla A.DC., 1845
• Tecoma leucoxylon (L.) Mart. ex A.DC., 1845
• Tecoma pentaphylla Juss. ex DC.

International Common Names

• English: pink manjack; pink poui; pink tabebuia; pink tecoma; poui; tecoma; white cedar; whitewood
• Spanish: roble; roble blanco
• French: le poirier des Antilles; poirier-pays

Local Common Names

• Saint Lucia: pòwyé

Summary of Invasiveness

Several Tabebuia species have been noted as invasive in parts of their native Caribbean range as well as where introduced to Pacific and Indian Ocean islands, mostly T. heterophylla, but also T. pallida and others. They are aggressive pioneer species, having rapid growth rates, forming a monoculture that casts a dark shade when established and few other species can survive under the canopy. They are valued for their timber and as attractive ornamental trees, and as such further introduction is likely, and it could easily become invasive in other humid, frost-free regions where it is not yet present, such as parts of Africa, Asia or Australia, or T. heterophylla may become invasive where it is already widely grown, such as in Florida, USA.

Taxonomic Tree

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Scrophulariales
•                         Family: Bignoniaceae
•                             Genus: Tabebuia
•                                 Species: Tabebuia heterophylla

Notes on Taxonomy and Nomenclature

There are at least 25 species of Tabebuia, all native to Central America, the Caribbean and northern South America, though others have noted as many as 100 species, evidence of the variability within the genus. Many are very similar morphologically and have sympatric native ranges, thus making distinctions difficult. As with other species in the genus, T. heterophylla (DC.) Britton is certainly a very variable species. 

Description

T. heterophylla is a small- to medium-size tree attaining a height of 18 m and a diameter of 60 cm, Leaves are palmately compound, opposite, with (1-) 3-5 leaflets, blades elliptic to oblanceolate or obovate, 6-16 cm long, leathery, acute to blunt at the tip, acute to rounded or oblique at the base; surfaces glabrous; margins entire; petiole 3-12 cm long. Inflorescences comprise one to several showy pink flowers borne in short terminal clusters, corolla sympetalous, somewhat bi-labiate, campanulate, 6-9 cm long, with 5 rounded lobes at the tip, pink or lavender with a pale yellow throat. Fruit is a narrow cylindrical capsule 7-16 cm long, opening along two seams to release the numerous winged seeds. Mature fruits, dark brown cigar-like pods, may be found on the tree during most of the year. They are 8-20 cm long and 6.5 mm in diameter, containing numerous winged seeds each about 2 cm long, there being approximately 70,000 seeds per kg (Weaver, 1990).

Plant Type

Distribution

T. heterophylla is native to most Caribbean islands (USDA-ARS, 2008). Kairo et al. (2003), however, mistakenly note it as exotic and naturalized in the Caribbean, and record it as naturalized and invasive in the Dominican Republic (i.e. within its native range), both as T. heterophylla and a synonym, T. pentaphylla. However, T. pentaphylla is also a synonym of T. rosea, native to Central America and northern South America, and further clarification appears warranted, which may include the acceptance of a larger native range than stated here. T. pallida is regarded as having a more restricted native range than even T. heterophylla, limited to the Windward islands only, from Grenada to Guadeloupe (USDA-ARS, 2008). Caution should be used when using common names, as many of those which describe T. heterophylla also appear to be used on several other Tabebuia species, such as white cedar or roble.

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

History of Introduction and Spread

No information is forthcoming on actual dates of introduction, though it may have been introduced only fairly recently to other islands. It was only noted as spreading and becoming invasive on some Pacific and Indian Ocean islands in 1999, notably in Hawaii, the Marshall islands, and the Chagos archipelago (PIER, 2008). The closely related T. pallida is also recorded as invasive in Mauritius (Parnell et al., 1989) and in the Seychelles (PIER, 2008). There are almost no records for T. heterophylla in mainland Africa and none in Asia or Australia, though it is likely that its presence is under-recorded. Missouri Botanical Garden (2008) have single records for T. heterophylla in Zambia and for T. pallida in Senegal, also records for T. rosea in Tanzania and Zimbabwe, India and Sri Lanka, the latter not included in the distribution list. T. chrysantha and T. donelli-smithii are also recorded as invasive on Puerto Rico (Kairo et al., 2003) and these and other Tabebuia species are likely to have been recorded as elsewhere. T. rosea has also been widely introduced but has not been recorded as invasive anywhere

Risk of Introduction

T. heterophylla scored a very low score in a risk assessment for the Pacific (PIER, 2008), meaning that it was not considered as posing a significant risk, even though it is recorded as invasive on some Pacific islands. However, noting its aggressiveness and pioneering nature, it and T. pallida could easily become invasive if introduced to countries where it is not yet present, such as Australia and South Africa. It is available for sale as an ornamental species and has been considered as a timber species for plantations, thus, risks of intentional introduction are high. Any of the other closely related species such as T. rosea may also be considered as potentially invasive.

Habitat

In its native Caribbean, T. heterophylla is particularly common in dry, coastal woodlands and in secondary forests, less commonly in dry or wet natural forests, and in some islands it can become widespread in abandoned pastures and secondary forests (Weaver, 1990). Some of the principle forest types in which it is found, for example, are dry evergreen forest in Puerto Rico and St Kitts-Nevis, dry scrub woodlands in the Lesser Antilles and British Virgin Islands, and it is also found (on one or two islands only) in bush land, fire grassland and standards, littoral woodland, secondary woodlands, seasonal forests, xerophytic rain forest and lower montane rain forest. In Puerto Rico, T. heterophylla regenerates and forms pure stands on grasslands and degraded soils, in particular on exposed upper slopes and ridges where competition from faster growing, larger, and more tolerant trees is lacking, and similarly, its persistence in the natural forest despite its slow growth, can be attributed to its ability to survive on poor sites where competition is minimized. It is tolerant of degraded sites and abandoned farm lands where it tends to form nearly pure stands (Weaver, 1990).

Habitat List

Biology and Ecology

Considerable variation can be seen in plant morphology from different parts of the native range, which has surely added to the taxonomic confusion surrounding this and related species. T. heterophylla typically has five leaflets in Puerto Rico, but in dry areas and coastal thickets in the Lesser Antilles, trees are shorter, fruits and seeds smaller, and leaflet number declines to three, or at times to a single leaflet, and another variation found in Guadeloupe, Dominica, and Martinique has a single, broadly elliptic leaf (Little and Wadsworth, 1964).

Flowering may commence just a few years after planting, with large white to light purple perfect flowers are borne few to several in terminal and lateral clusters, or occasionally as individuals. Fresh seed germinate readily and at up to 100%, whereas after 3 weeks seed viability may fall to half, and no seed germination may be observed after 5-6 weeks (Weaver, 1990). However, under low temperature storage (at 5°C), seeds retained 100 germination capacity for up to 240 days (Huc and Bariteau, 1987). T. heterophylla can also be vegetatively propagated easily from shoot cuttings (Huc and Bariteau, 1987).

In Puerto Rico, flowering is mostly in the dry spring when all the leaves also fall, with fruits borne in May and June and fruit fall from July to September (Weaver, 1990), whereas in Guadeloupe, it was noted that flowering and fruiting had several peaks in wet zones but only a single peak in the dry zone (Huc and Bariteau, 1987). However, T. heterophylla is not a copiously-fruiting species in comparison with other trees from similar vegetation types. Seeds germinate in open areas and form dense stands of seedlings, T. heterophylla being an aggressive pioneer, especially in seedling and sapling stages. In open fields it regenerates well developing into a dense stand of seedlings, but after which it appears to stagnate, which may be due some combination of shallow, infertile soils, exposure and density of the seedling stands (Weaver, 1990). From data from plantations, tree growth was found to be 1 m in height and 1 cm in diameter per annum, though this could be reduced to one third in natural forests. Shaded seedlings grow very slowly or not at all, as in natural conditions seedlings are capable of surviving shade for years with no appreciable growth, and as such are classified as shade intolerant (Weaver, 1990).  

Climate

Air Temperature

Rainfall

Rainfall Regime

Soil Tolerances

Soil drainage

• free
• impeded
• seasonally waterlogged

Soil reaction

• acid
• alkaline
• neutral

Soil texture

• heavy
• light
• medium

Special soil tolerances

• infertile
• shallow

Notes on Natural Enemies

No pests are observed in natural forest situations, however, branches of roadside trees in Puerto Rico are often deformed into a witches' broom appearance, apparently by a virus possibly transmitted by the leaf hopper Protalebra tabebuiae, which also defoliates the tree or causes the leaves to turn yellow and fall prematurely (Little and Wadsworth, 1964). Few other diseases have been identified, and then only rarely, including a dieback disease Botryodiplodia spp.,a shoot borer Pachymorphus subductellus and the dry wood termite Cryptotermes brevis (Weaver, 1990).

Means of Movement and Dispersal

The winged seed are dispersed by wind. When the fruit capsule splits, seeds are dispersed up to or over 100 m depending upon weather conditions (Weaver, 1990).

Used as a ornamental and forestry tree, intentional introduction is the most likely means for long-distance dispersal. It was probably introduced to Florida, USA for its showy pink flowers.

Pathway Causes

Pathway Vectors

Economic Impact

No data on economic impacts, positive from trade in ornamental plants or forestry production, or negative from control efforts, etc., are forthcoming.

Environmental Impact

T. heterophyllaand the closely related T. pallida both have clear environmental effects, due to shading, and the fact that trees are deciduous and thus the thick litter layer produced may also prevent the growth of native seedlings

In Mauritius, a number of endemic plants are threatened by the closely related T. pallida (Parnell et al., 1989). It is also possible that in regions where it is introduced, species sharing the same ecological niche, i.e. pioneer species, could be displaced if T. heterophylla proves to be a better competitor, as for example, was found in West Africa following the invasion of Cecropia peltata.

Risk and Impact Factors

• Invasive in its native range
• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Pioneering in disturbed areas
• Highly mobile locally
• Fast growing
• Has high genetic variability

• Ecosystem change/ habitat alteration
• Modification of nutrient regime
• Modification of successional patterns
• Monoculture formation
• Reduced native biodiversity
• Threat to/ loss of endangered species
• Threat to/ loss of native species

• Competition - monopolizing resources
• Competition - shading
• Rapid growth

• Highly likely to be transported internationally deliberately
• Difficult to identify/detect as a commodity contaminant
• Difficult to identify/detect in the field

Uses

T. heterophylla heartwood is light brown or golden, grain straight to interlocked, seasoning rapidly with little warping and is fairly easy to work, The wood has a specific gravity of about 0.55, is tough and strong for its weight, and is widely used for flooring, furniture, cabinetwork, decorative veneers, interior fittings, tool handles, boat building and sports equipment, with lower quality wood used for boxes, crates and shuttering, and sometimes as round wood for posts and poles (Little and Wadsworth, 1964). Its large showy, pink flowers and narrow, columnar crown give rise to its value as an ornamental tree, and it is also acknowledged as a honey plant. T. heterophylla is also used as a shade tree for coffee and cocoa (as T. pentaphylla) in Venezuela, and planted on poor sites to provide cover and to improve the soil (Weaver, 1990).

Uses List

Environmental

• Agroforestry
• Amenity
• Ornamental
• Revegetation

Fuels

• Fuelwood

Human food and beverage

• Honey/honey flora

Materials

• Wood/timber

Wood Products

Boats

Containers

• Boxes
• Crates

Furniture

Roundwood

• Posts

Sawn or hewn building timbers

• Carpentry/joinery (exterior/interior)
• Flooring
• For light construction

Veneers

Woodware

• Industrial and domestic woodware
• Sports equipment
• Tool handles
• Wood carvings

Similarities to Other Species/Conditions

T. heterophylla is sometimes confused in the literature with the closely related T.pallida (Lindl.) Miers, as the latter has sometimes been used as a synonym, and with T. pentaphylla Hemsl. which is now treated as a synonym (but not T. pentaphylla auct.) (USDA-ARS, 2008). They appear to share similar environmental requirements and sympatric native ranges. Both have pink flowers thus are grouped together by some horticulturalists, who differentiate these from other yellow-flowering species, though T. pallida may also have white flowers. Foliar morphology is also similar, making differentiation more difficult. Ecologically, Tabebuia spp. share similar native ranges and habitats and pioneer qualities with a number of species of Cecropia and Tecoma (both also sometimes called ‘trumpet trees’), but T. heterophylla is generally differentiated morphologically by its opposite, palmately compound leaves, furrowed bark, and narrow, columnar crown.

Prevention and Control

Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.

No specific management information is available on control of T. heterophylla. As with all plants they can be dug up by hand or mechanically when small, and either cut, or cut plus a herbicidal stump treatment when larger, although its ability to coppice has not been ascertained. However, as a pioneer species in its native range, it may be assumed that, following initial invasion of disturbed sites that may lead to up to 100% cover with T. heterophylla, ecological succession will see a natural reduction over time, with a gradual increase in the numbers and frequency of native species.

References

Huc R; Bariteau M, 1987. New data on vegetative propagation and propagation by seed of Tabebuia heterophylla. (Tabebuia heterophylla (DC.) Britton; données nouvelles sur la reproduction sexuée et végétative.) Annales des Sciences Forestières, 44(3):359-363.

ISSG, 2005. Global Invasive Species Database (GISD). Auckland, New Zealand: University of Auckland. http://www.issg.org/database

Kairo M; Ali B; Cheesman O; Haysom K; Murphy S, 2003. Invasive species threats in the Caribbean region. Report to the Nature Conservancy. Curepe, Trinidad and Tobago: CAB International, 132 pp. http://www.issg.org/database/species/reference_files/Kairo%20et%20al,%202003.pdf

Little EL; Wadsworth FH, 1964. Common trees of Puerto Rico and the Virgin Islands. Agric. Handb. U.S. Dep. Agric, 249:548 pp.

Missouri Botanical Garden, 2008. Tropicos database. St Louis, USA: Missouri Botanical Garden. http://www.tropicos.org/

Parnell JAN; Cronk Q; Jackson PW; Strahm W, 1989. A study of the ecological history, vegetation and conservation management of Ile aux Aigrettes, Mauritius. Journal of Tropical Ecology, 5(4):355-374.

PIER, 2008. Pacific Islands Ecosystems at Risk. USA: Institute of Pacific Islands Forestry. http://www.hear.org/pier/index.html

Seddon SA; Lennox GW, 1995. Trees of the Caribbean. London, UK: MacMillan Education Ltd.

USDA-ARS, 2008. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2008. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/

Weaver PL, 1990. Agriculture Handbook 654. Washington DC, USA: USDA-FS.

Distribution References

CABI, Undated. CABI Compendium: Status inferred from regional distribution. Wallingford, UK: CABI

CABI, Undated a. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI

Kairo M, Ali B, Cheesman O, Haysom K, Murphy S, 2003. Invasive species threats in the Caribbean region. Report to the Nature Conservancy. In: Invasive species threats in the Caribbean region. Report to the Nature Conservancy. Curepe, Trinidad and Tobago: CAB International. 132 pp. http://www.issg.org/database/species/reference_files/Kairo%20et%20al,%202003.pdf

Missouri Botanical Garden, 2008. Tropicos database. In: Tropicos database, St. Louis, USA: Missouri Botanical Garden. http://www.tropicos.org/

Parnell J A N, Cronk Q, Jackson P W, Strahm W, 1989. A study of the ecological history, vegetation and conservation management of Ile aux Aigrettes, Mauritius. Journal of Tropical Ecology. 5 (4), 355-374.

PIER, 2008. Pacific Islands Ecosystems at Risk. In: Pacific Islands Ecosystems at Risk, USA: Institute of Pacific Islands Forestry. http://www.hear.org/pier/index.html

USA, USDA-ARS, 2008. Germplasm Resources Information Network (GRIN). Online Database. In: Germplasm Resources Information Network (GRIN). Online Database, Beltsville, USA: National Germplasm Resources Laboratory. http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl

USA, USDA-NRCS, 2008. The PLANTS Database. In: The PLANTS Database, Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov

Weaver P L, 1990. Tabebuia heterophylla (DC.) Britton. In: Silvics of North America. Washington DC, USA: Forest Service, USDA.

Links to Websites

Contributors

29/02/08 Original text by:

Nick Pasiecznik, Consultant, France

Distribution Maps