Rare Listea has potential for furniture and pharmaceuticals and, maybe, Melbourne gardens

A lot of journal space has been occupied by the oils of Litsea cubeba. This deciduous shrub or small tree from roadsides and stream banks in southern and south-eastern, Asia has a long history in Chinese medicine and cooking.

It is widely grown in tropical and subtropical China for its fruits (bi-cheng-qie when dried) and roots (dou-chi-jiang), and is used extensively for ailments such as 'coronary disease, cerebral apoplexy, asthma and rheumatic arthritis'. Many of the recent scientific papers demonstrate active antibacterial properties of oils from the plant.

Citrol, one of those oils, is also extracted from flowers, leaves and fruits to flavour food, cigarettes and cosmetics. On top of all that, the wood is used for furniture and cabinet-making.

Litsea is in the family Lauraceae, along with the familiar Bay Laurel (Laurus nobilis) and another few thousand species. There are up to 200 species of Litsea, including a few (12) in Australia and the Americas, but mostly in Asia, with 74 in China (47 of them only found in that country).

One of the endemic Chinese species is Litsea auriculata (illustrated here), not so popular in the scientific press as Litsea cubeba but it is a useful plant and there are studies out there. In the Flora of China you can read 'the wood is yellow, heavy, and dense, and is used for making furniture, etc. The root bark, leaves, and fruits are used medicinally.'

Litsea auriculata is rare and under threat in its natural habitat, a few high mountain areas near the border of the Anhi, Zhejiang and Henan Provinces. Apparently, most remaining populations consist of less than 40 trees.

I saw one of these populations, along with other rare and intriguing species (such as a possibly native location for the gingko, and huge cryptomeria), in the Tree King Scenic Area of the Tianmu Mountain an hour or so drive out of Hangzho, in the Zhejiang Province.

These eastern Chinese populations are the remnant of a more widespread distribution, with habitat loss the main reason for its recent demise. Now that the populations are small and separated, climate change is a risk, as is the low viability of pollen in the wild.

There were certainly plenty of flowers on the trees I saw. The cluster of flowers is a little like that found in the carrot family, although in this case it is usually described as a pseudo-umbel rather than (dinky-di) umbel. Flowers are male or female, not both, and pollinated by insects. 

As you can see in the photographs above (a little dark due to light limitations at the time), Litsea flowers while the leaves are still absent. This is early spring, April, and I was escorted through the stand with the Director of Hangzhou, Jinliang Yu, at the right of this picture, with colleagues photographing my featured plant.

We don't grow any Litsea in Royal Botanic Gardens Victoria. Presumably our climate is not (sub)tropical enough. At the moment. The changes to the world's climate threatening the survival of Litsea auriculata in the wild may allow it to grow, eventually, in Melbourne.