Xanthostemon chrysanthus

Xanthostemon chrysanthus.

This north Queensland native has many common names including Penda, Golden Penda and River, Brown or Black Penda.
It is a very common tree in Brisbane especially in parks and on roadsides.
It is a multi-stemmed shrub or a tree up to 10 (20) m high.
The rough bark cracks and fissures exposing a reddish under layer then peels off.

The shiny dark green leaves are crowded at the branch ends.
On a short petiole they are lanceolate or elliptic and 10 to 15 cm long by 3 or 4 cm wide.
The tip is pointed and there are oil glands.
The very glossy new leaves are red.

There are numerous small axillary inflorescences near the branch ends.
Each has up to 10 flowers on a 1 to 1.5 cm long peduncle.
Flowers, up to 1.5 cm across are on a pedicel with small green bracteoles.
Collectively all the small inflorescences form a large cluster (commonly called an inflorescence) up to 20 cm across.

The sepal and petal bases are fused to form a bell-shaped hypanthium (calyx tube) up to 6 mm wide.
The up to 5 ovate to triangular sepal lobes, around 3 mm long are often unequal.
The hypanthium and lobes have no hairs but are dotted with oil glands.
The 5 cupped petal lobes, around 8 mm long are round with a narrower base.
They are a bright yellow with pink or orange oil glands.

The up to 50 stamens, in one whorl have bright yellow filaments up to 3 cm long.
The oblong 1.5 mm long anthers have a depression in the basal connective into which the filament inserts.
Anthers open inwards through longitudinal slits.

Up to the lower one third of the ovary is fused to the hypanthium with the rest just being enclosed by it.
The hairless green ovary, around 3 mm long is dotted with oil glands.
It has 3 or 4 locules each with numerous ovules.
In each locule the flat ovules are packed in a single ring around the placenta.
The yellow style, up to 4.5 cm long has a small stigma.

The fruit are roughly spherical loculicidal capsules up to 1.4 cm wide.
The enlarged hypanthium, with the sepal lobes is attached to the base.
The flat seeds are about 4 mm long.

There are a number of dwarf cultivars such as ‘Baby Penda’, ‘Expo Gold’, ‘Fairhill Gold’ and
    ‘Little Goldie’ that grow from 1 to 3 or 4 m high.