Hong Kong's Wild Stars

The Fighter in the Ferocious Flow - Looking Glass Tree

Jun 2019
Author: Green Power
The buttresses roots of Looking Glass Tree Heritiera littoralis
The buttresses roots, which grip the loose soil, play the key role in stabilising the tree.

While the rest are dead in the waters of a shoreline washed by waves, a survivor stands firmly and multiplies on the unstable land. The Looking Glass Tree (Heritiera littoralis) toughs it out in the dire condition through having powerful buttresses roots and reflective leaves. What’s more, these trees aforest a lush shoreline by their fruits simply drifting on the tide!

Looking Glass Tree, an evergreen tree in the family Sterculiaceae, is one of the eight true mangrove species in Hong Kong. Compared to the other true mangroves, such as Black Mangrove (Avicennia marina) and Kandelia (Kandelia obovate), Looking Glass Tree grows closer to the land. Despite the fact that Looking Glass Tree avoids the most powerful waves, living in the intertidal zone is no piece of cake. So, how does Looking Glass Tree take the dire straits in its stride?

The Formidable Flairs

Looking Glass Tree grows to become like a rocket of steel – a sturdy tree trunk as a robust fuselage, and the powerful roots as the steady fins. The roots expand from the ground upwards, forming triangular fin-like buttresses roots. The major function of the buttresses roots is to anchor the tree in the loose soil. The larger area the roots grasp, the taller the tree grows.

The silvery scales on the leaf base of Looking Glass Tree Heritiera
To help retain moisture, the silvery scales on the leaf base beat the heat by reflecting excessive sunlight.

Turning over a leaf of the Looking Glass Tree, you may find a layer of fluorescent silvery white underneath its ordinary face. This is as suggested by its Chinese common name. The glassy layer is more than an outer beauty - the tiny scales stabilise the tree’s temperature by reflecting excessive sunlight from the water surface, helping retain moisture.

Looking Glass Tree Heritiera littoralis fruits falling on the grassland
The fruits resemble Ultraman’s head, don’t they?

Thanks to its fibrous nature, the fruit of Looking Glass Tree can drift unremittingly along the seashore. Furthermore, in order to thrive on the coast, the oval fruit has to secure itself in the correct direction in order for its young leaves to grow upwards, and its roots settle into the ground. That’s the secret behind the little ridge on the surface of each fruit. Because of its remarkable appearance, the fruit of Looking Glass Tree has always been mocked as “Ultraman Fruit”. If you know the character Ultraman, what do you think?

A Vigorous Vintage Touch

Although Looking Glass Tree does not stand on the corner of the street, you may easily come across one by stepping closer to coastal areas. Situated in Double Haven, a silken river passes through the picturesque Lai Chi Wo Village. Its brackish intertidal zone best suits the growth of Looking Glass Trees. The hamlet’s multi-century development eventually reached its zenith, before it gradually declined along with time and tide. In the face of empty houses and rusty chimneys, the Looking Glass Trees still grow with vitality, welcoming visitors.