Tecoma stans (L.) Juss. ex Kunth

Cotyledons

Cotyledons with two rounded lobes.

Stem

Stem is solid and cylindrical. The younger stems are smooth, glabrous and greenish in colour. They are slightly quadrangular and turn pale brown or reddish-brown in colour as they age. The bark on the main stem is light brown to pale grey in colour, furrowed, and relatively rough in texture, covered in light greyish to brown barks.

Leaf

Leaves compound, opposite, 10-25 cm long, with 3-13 leaflets, but usually 3-7 leaflets ; carried by a petiole 3-5 cm long. Leaflets lanceolate to elliptic, 2-10 cm long and 1-4 cm wide, apex long-acuminate, base cuneate. Margins irregularly and finely toothed. Both sides of the leaf blade are smooth and mostly glabrous, though a few hairs may be present on the undersides near the midrib.

Inflorescence

Inflorescence erect or inclined several-flowered clusters (5-15 cm long), produced terminally (at the ends of the branches), and then later, in the leaf axils near the tips of the branches.

Flower

Flowers showy bright yellow, tubular (trumpet-shaped), borne on short pedicels somewhat curved or twisted. Corolla tube 3-5 cm long with five rounded lobes, 8-30 mm long. Presence of several faint reddish lines in the throat of the flower, which is slightly ridged and hairy.

Fruit

The fruits are large, linear capsules, somewhat flattened, 10-20 cm long and 0.5-2 cm wide, brown at maturity, they split open to release numerous seeds.

Seed

The seeds are very flat, oblong in shape (7-8 mm long and about 4 mm wide), and have a transparent wing at each end (the size of entire seed including the wings is about 20 x 6 mm).

Mayotte: Tecoma stans flowers from March to November and fruits from April to December.
Nicaragua: Tecoma stans flowers from September to May and bears fruit from December to April.
New Caledonia: Flowering of Tecoma stans extends from the end of the rainy season until the dry season when fruiting takes place. The seeds produced in November germinate from the first rains.
West Indies: Tecoma stans flowers almost all year round, especially from October to April.

Tecoma stans is a weed of roadsides, riparian zones, open woodlands, grasslands, forest margins, waste areas, rocky places, sandy lake shores and disturbed sites in tropical and subtropical environments. It quickly become very abundant in overgrazed pastures and disturbed habitats both within and outside its natural range. The most severe invasions in Brazil, northern Argentina and South Africa are in subtropical climatic zones of moderate to high rainfall, often along drainage canals.

Mayotte: T. stans is cultivated in gardens for its yellow flowers. It is also naturalized on the rocky cliffs of Dzaoudzi and in other degraded xerophilous environments of the coast. It is not recorded in the crops.
New Caledonia: The ecological plasticity of Tecoma stans is high in dry to moderately dry areas.
Reunion: Tecoma stans is cultivated in gardens and naturalized and invasive in the dry region (especially in the slopes of the Saint Leu area).
South Africa: Tecoma stans is an exotic species that thrives along watercourses, gardens, urban open spaces and roadsides, mainly in warm regions. In KNP, Tecoma stans occurs in forested areas, villages and roadsides.
West Indies: Tecoma stans is a native species that thrives in dry coastal environments at altitudes of 0 to 50 (150) m, mainly volcanic. It is sometimes grown as an ornamental.

Overall harmfulness

Tecoma stans is a major invasive plant in South Africa, Argentina, the United States and the Pacific, where it is one of 300 major invasive species. It is an aggressive invasive plant that quickly competes with natural vegetation and grasslands. It can be considered a transformative species that reduces biodiversity and destroys natural resources. It has been planted in gardens as an ornamental species and as a street tree, but has become a problem in parts of tropical and subtropical Africa, Asia, South America, the Pacific Islands, Australia.

Local harmfulness

New Caledonia: The seeds germinate from the first rains, Tecoma stans is then able to constitute very quickly invasive populations. It is considered invasive in New Caledonia where it forms dense and isolated stands on the west coast. It is currently expanding particularly in pastures where it is a serious competitor species for forage species for access to light, water and nutrients. Measures must be taken quickly; an information and eradication campaign would be desirable accompanied by monitoring of its extension throughout the territory.
Reunion Island: Tecoma stans is naturalized and invasive in the dry region of the island (especially in the region of Saint Leu where it forms continuous clumps at low altitude in the natural vegetation and anthropized environments).
South Africa: Tecoma stans is naturalised and invasive in the eastern part of the country. It forms a clustered bush and completely replaces the indigenous vegetation. It competes with and has the potential to replace indigenous species. Can invade hot and dry savanna where it may reduce grazing for domestic and wild animals. It occurs in Eastern Cape, KwaZulu-Natal, Mpumalanga, Gauteng, Limpopo Provinces.

Herbarium pictures ReCOLNAT: https://explore.recolnat.org/search/botanique/simplequery=Tecoma%2520stans