T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Lagunaria patersonia (Norfolk Island Hibiscus)

Kingdom: Plantae
(Unranked): Angiosperms
(Unranked): Eudicots
(Unranked): Rosids
Order: Malvales
Family: Malvaceae
Genus: Lagunaria
Species: L. patersonia
Binomial name: Lagunaria patersonia
Common names: Pyramid tree, Norfolk Island Hibiscus, Itch Tree, Cow Itch Tree, Itchy Pod Tree, White Oak, White Wood Tree, Queensland Pyramid Tree, Sally Wood, Sugar Plum Tree, Tulip Tree, Norfolk Hibiscus, Primrose Tree, Pyramid tree, Queensland white oak.

Lagunaria patersonia the only species in the genus Lagunaria. This Australian plant is endemic to Lord Howe Island, Norfolk Island and parts of coastal Queensland. Though it is commonly called the “Norfolk Island Hibiscus”, it is however not a true Hibiscus, but does belong to the same plant family, Malvaceae. 
Lagunaria patersonia is a fast growing pyramidal tree (H15m by W7m),
L. patersonia leaves (5-10cm long) are thick, entire, oval and are olive green in colour. The juvenile leaves have a silvery tomentose on the undersides which later matures a grey-green. The leaves are 5-10cm long.
It develops hibiscus like pink flowers in summer and early autumn. These flowers are 2.5-5 cm across and are borne in the leaf axils, on short, thick, pedicels. The petals are pale pink or mauve in colour, fading to white and are of waxy texture. The anthers are borne along much of the length of staminal column and are gold to orange in colour. The style is white or cream in colour and club shaped at the top with 5 radiating stigmatic lobes.
The flowers are succeeded by brown capsules. The interior of these seed capsules are filled with white hairs which are irritant giving rise to a common name "Itchy Pod Tree".
In New Zealand a fungal pathogen of the genus Hoheria and Plagianthus (Nectria hoheriae) has jumped to Lagunaria specifically in the Nelson and Wellington areas which is the southern fringe in which Lagunaria is hardy.

Photographed at Pukekura Park, New Plymouth, February.

The silvery tomentose on the undersides of the young leaves can be seen.


Underside of a leaf.

The dried seed capsules

The seeds inside an opened capsule.