An infant Gargantua
One of the biggest tree species downtown Chiang Mai is the rain tree (Samanea saman=Albizia saman, Fabaceae, Mimosoidae). Being an exotic import (South America) the largest specimens can be found along the Ping river in the former western quarters. One of the largest grows in the garden of the French library (it is still French territory) next to the Chedi Hotel. My friend Don Cox measured the trunk and found it is 11 m in circumference at breast height. Really tall trees abroad can reach 60 m in height and have an equal diameter of the crown.
At Dokmai Garden we have a young rain tree which is about the same age as Mika, 4.5 years. It is already 12 meters tall and has a trunk circumference of 104 cm at breast height.
The end pair of leaflets are diamond-shaped and a typical feature to recognize a young seedling. The tree flowers right now, and they provide a nice nectar for sunbirds and insects. To admire the flowers, you need to watch the tree from above. One good spot is the Chiang Mai Ram hospital. While waiting for the elevator a few floors up you have a nice sight of a fluffy green cloud of leaves covered with red blossom similar to fiber optic decoration.
The fruit, a bean pod, looks like a hotdog somebody forgot too long on the grill, and then saved in the fridge over night. The inside has a surprisingly appealing fragrance of fermented fruit, and the seeds are embedded in a sticky pulp. Ketsanee said the pigs like to eat the pods, so I brought them fruits and leaves. On the way to the pig pen our water buffalo came up to me with the determined face of a connoisseur. I thought ‘why not’ and offered him a leafy young twig. He eagerly took it but spit it out with the disappointment of a child tasting beer believing it was soda. Among pigs I am known as ‘the food guy’ so I was greeted with wagging tails and excited grunts. I first threw in the leafy twigs but these gastronomers did not even bother to look at them. Then I threw in a generous harvest of pods and they ate them like candy, even fought over them. Crunch, crunch – aroi mak!
At Dokmai Garden, as well as at the province government in Mae Rim and at the Dara Devi hotel, the rain trees have long shallow roots running like mountain ridges through the lawn. I believe this is an effect of the lawn irrigation, as specimens in unmanaged areas do not have these shallow roots but go deep to find water. The rain tree is therefore only suitable in large gardens far away from houses, and in areas where you do not irrigate. It is highly tolerant to drought, and folds its leaves at dusk to reduce water losses. A most appealing feature is the elegant shape of the crown. There is hardly no need to prune it, it is a natural beauty, a huge parasol and a home tree.
If you want a tree, simply pick seeds under a big mother tree, or ask for a free seedling at any of the many Thai governmental tree nurseries or dig up one of the many seedlings found along roads and paths near human habitation. A Central Thai name is ‘chamchuri’ and a northern Thai name is ‘sam sa’. The English name ‘rain tree’ alludes to the ‘rain’ caused by exudates of sap-sucking insects such as the lac insect.
Text & Photo: Eric Danell