Recently the Cassia javanica var. indochinensis (節果決明 Rainbow Shower / Pink-and-white Shower) in front of The Murray Hong Kong (formerly Murray Building 美利大廈) has drawn much attention over social media. Many people including some professional photographers rushed to the spot to capture the full bloom of the chains of pink petals with contrasting yellow stamens.
The popularity of this tree is due to its unique
mass of pinkish blossom almost like a cherry tree and also the rarity of the
species in Hong Kong. The tree is
believed to be a variety of a quite intra-specifically diverse tree, Cassia
javanica (爪哇決明 Pink Shower)
but the real identity of this particular individual is still more or less a mystery. It is said that there are only two or three 2-3
individuals of this species in Hong Kong.
There is not much information about this variety if one searches its
name over the web (and it appears that nearly all relevant records come from local
websites!). The name is commonly
considered as a synonym of other subspecies by authoritative websites, although
debate continues regarding differences in their appearance.
Regardless of its identity, this iconic tree
has several noteworthy features. Fortunately
it was retained and protected meticulously when the 43-year-old government
building was converted into the current hotel. Going further back, before the
original Murray Building was completed in 1969, the tree is believed to have
been standing at the same spot when this was part of Murray Barracks (美利兵房). Research
by this author revealed that the tree’s history can be traced back at least to just
after WWII, when the British army handed over this piece of land (formerly the
military gymnasium and then detention blocks) to the Hong Kong Girl Guides for
their first headquarters. The tree has witnessed the dramatic transformation of
Central district and the city as a whole.
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| Map of Detention Camp (bottom right) in 1959 showing position of Sandiland Hut of HK Girl Guides (circle as tree position; Sandiland Hut below circle) Photo source: 蔡超穎、宋樁蕾、何卓男、葉趣林、黃亦莊(2014). 戰爭與和平: 由美利兵房土地用途變遷看香港城市發展與空間規劃. 香港歷史博物館第八屆歷史照片研究比賽參賽作品, 香港. |
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| Sandilands Hut after
WWII showing leaves of Cassia on the top right Photo source: Anon. (2017). The Hong Kong Girl Guides: A Century of Work, Action and Achievement. HKGGA Centenary Brochure, Hong Kong |
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| A photo of 1954 showing a tree which is the approx. location of the current OVT Photo source: Gwulo.com |
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| A photo of 1960 showing a tree which is the same location of the approx. OVT. D: Detention Camp Photo source: Gwulo.com |
The other special feature of this tree is that it is currently the only Registered Old and Valuable Tree (OVT) maintained under private land lease (registered as LandsD(leased) CW/1), owing to the story that the tree was originally government land. The care shown to this OVT by the current maintenance agent (the hotel) would form a very good reference for future OVTs on private land (if any).
Many species from the genus Cassia are very showy. Apart from the original species Cassica javanica (Pink Shower) another close relatives of Rainbow Shower is very common in Hong Kong – the Golden Shower (Cassia fistula 豬腸豆/臘腸樹), which is famous for its drooping chains of golden flowers. Typically they bloom in May after the Rainbow Shower, but this year many were already in flower in mid-April if not earlier.
