Peltophorum pterocarpum

Peltophorum pterocarpum.

Family Caesalpiniaceae (or Fabaceae s.l. > Subfamily Caesalpinioideae).
The number of Peltophorum species is uncertain withfigures ranging from 5 to 15.
Peltophorum africanum and Peltophorum pterocarpum are seen in Australia.

Common names for Peltophorum pterocarpum include Copperhead, Yellow flame tree and Yellow poinciana.
Native to S.E. Asia it is naturalised in Northern Australia.
It is seen in Brisbane as an ornamental or shade tree in parks and streets.
They are semi-evergreen trees usually around 15 to 25 m high.
The base is sometimes buttressed and the branches are spreading.

The alternate, bipinnate leaves are up to 60 cm long with 15 to 20 pairs of pinnae.
Each pinna has 10 to 20 pairs of leaflets on petiolules under 1 mm.
The ovate leaflets are up to 25 mm long and 8 to 10 mm wide.
The base of the leaflet is asymmetric and the tip has a small notch.
Small twigs and new leaves are densely covered in brown hairs.

Erect inflorescences are branched spikes up to 50 cm long.
The stalks and buds are covered in rust-coloured hairs.
The flowers, with parts in 5’s, are up to 4 cm across.

The bases of the sepals are fused into a short tube and the lobes bend backwards.
There are hairs on the outer surface.
The crumpled yellow petals, with wavy edges, are around 1.6 cm long.
Both surfaces have brown hairs on the narrow base and onto the round upper section.

There are 10 free stamens with a large clump of brown hairs near the base.
The dorsifixed anthers open via long slits.
The ovary is on a gynophore and both are covered in dense brown hairs.
The smooth style has a large, green stigma.

The fruit pods, with flattened edges, are up to 10 cm long and 2.5 cm wide.
They mature from red to black.
Each has up to 5 seeds around 1 cm long.

Peltophorum africanum is similar but:

  • they are smaller trees (10 – 15 m high) and the leaves only have 4 to 10 pairs of pinnae,
  • the leaflets are smaller (7 mm long x 2 mm wide) and the flowers are smaller (2 cm wide),
  • the yellow petals have whte hairs at the base and
  • the fruit pods usually only have 1 or 2 seeds.

Leopard trees (Ceasalpinia ferrea) have similar small, yellow flowers with 5 petals
    but their bark is very distinctive and the stems and flowers have no hairs.

J.F.