Common Names: Jatobá, West Indian Locust Bean, Courbaril, Guapinol, 孿葉豆, 南美叉葉樹
Scientific Name: Hymenaea courbaril L. [1]
Family: Fabaceae/Leguminosae (Subfamily: Detarioideae) [2]
Natural Distribution: Central to South America, including some Caribbean islands. [3, 4]
Natural Habitat: Tropical rainforest, usually along riverbanks, tropical dry forests, subtropical rainforests and tropical montane forests. [3, 5]
Description: Evergreen tree that can grow to 40m tall. Larger specimens with trunk of around 1m in diameter. Bark whitish and rather smooth. Leaves bifoliate smooth and can grow up to 12 cm long and 7 cm wide. [5]
Flower: Inflorescence terminal. The creamy white flowers are bisexual. The flower has 4 distinct sepals, 5 petals and around 10 stamens. [5]
Seeds: Fruits at about 10 years old in natural environment. [5] Fruit pods are oblong can get more than 10 cm long. Orthodox brown seeds with hard seed coats are about 2cm in length and are surrounded by a creamy and powdery pulp layer. In their native range in the Amazon, the seeds can be dispersed by agoutis and other terrestrial mammals.
In modern society, this hardwood tree is most commonly used as timber, which yields excellent durable wood. In their native range, locals use the gum from this tree. The bark is reported to be used by indigenous Amazonians for medicinal purposes. [5] The pulp is edible raw or cooked and is described as sweetish but powdery.
I was really fortunate to be able to collect the fruits of jatobá. In 2019 January at Meinong Shuangxi Tropical Arboretum in Kaohsiung, Taiwan. A bit of scrambling in the woods allowed me to find some seeds. It appears that the tree does not fruit every year at this location or at least the production varies considerably every year, it may be affected by precipitation levels.
As the pulp is quite starchy, the fruit attracts a lot of insects and the seed pod seems to rot readily after rain. Pre-treatment is required to germinate if it has been stored for quite a while. For me, storing at ambient temperature, I was still able to germinate the seed one year later. The fruit pods are very robust and sturdy, I had to leverage the force generated by closing a door (by the hinge) to crack the pod open.
Once the seed coat is nicked or scarred, I place it in lukewarm water for a day (I did this on warm days, i.e. summer), then placed it straight into the Sphagnum moss. Conditions in the Sphagnum moss was likely 29°C/84.2°F and more than 80% in humidity. The seed will germinate and expand and the seed coat will start to break open. It should then take maximum a week for the root to appear.
I waited until the root is more than 5cm long, then transferred it into growing media. I used a mixture of Akadama and regular potting mix from supermarkets (about 1:1 ratio). I started to use more Akadama although a little more expensive because I find that it just drains better. I postulated that some of my past plants have died due to really bad growing medium, which begins to smell bad after a year, probably there was rotting as well. Hopefully this Akadama usage will solve this short-term issue, but repotting is probably still required every few years. The plant was left in the balcony of the apartment, which experiences midday partial sunlight, 29°C/84.2°F and around 50-60% humidity.
In October, the plant’s growth has stalled, with daily temperatures ranging from 23°C/73.4°F to 25°C/77°F and low luminosity due to cloudiness and rain from the monsoon. Humidity has consistently stayed over 70%.
Then winter came. The plant was brought indoors where the temperature and humidity were consistent, usually at around 15°C/59°F to 20°C/68°F, but the plant still managed to grow new shoots. The 2021 Chinese New Year period was relatively warm, allowing the plant to pick up growth speed, but when the temperatures dipped again, the growth halted.
It really is a nice neat plant. Might even be suitable as an ornamental plant while juvenile.
REFERENCES
- http://www.worldfloraonline.org/taxon/wfo-0000168642
- Serbin GM, Machado RM, Pinto RB, Diniz Filho JAF, de Azevedo Tozzi AMG, Forni-Martins ER, et al. Karyological traits related to phylogenetic signal and environmental conditions within the Hymenaea clade (Leguminosae, Detarioideae). 2019;39:125462.
https://doi.org/10.1016/j.ppees.2019.125462 - https://raywang1016.pixnet.net/blog/post/467747162
- http://tropical.theferns.info/viewtropical.php?id=Hymenaea+courbaril
- http://apps.worldagroforestry.org/treedb/AFTPDFS/Hymenaea_courbaril.PDF
RAINFOREST WISH 