Pithecellobium dulce has several common names. In Mexico, I called it guamúchil. In the Philippines, I began to call it kamatsili. Two of its English common names are monkeypod and Manila tamarind, according to StuartXchange.
The name guamúchil shows that this species is a tree, since the first part of this common name is derived from the Nahuatl word cuahuitl, which means “tree.” Let us take a look at this species from a scientific point of view.
The current scientific name of this species is Pithecellobium dulce (Roxb.) Benth. According to Kew, the name in parenthesis refers to William Roxburgh, a native of Scotland who spent a lot of time in India. According to StuartXchange, he originally called this species Mimosa dulcis. From the fact that George Bentham’s name is cited without parentheses, I deduce that he was the scientist who eventually transferred this species to the genus Pithecellobium.
Because the new genus is a neuter noun while Mimosa is feminine, the form of the specific name, which is a modifying adjective grammatically, is changed from the feminine form dulcis to the neuter form dulce.
This species belongs to the family Leguminosae, otherwise known as Fabaceae. Peas and beans belong to this family. The tamarind also belongs to this family. However, the so-called Manila tamarind is not really a tamarind.
Pithecellobium dulce is a thorny tree that is sometimes grown as a protective hedge. Under optimal conditions, it grows fairly tall. Figures given on the Internet vary. According to Purdue University, it reaches a maximum height of “up to 20 m. or more.” Other sources offer more conservative figures.
According to FAO, the “leaves are paripinnate with a single pair of pinnae and one single pair of leaflets per pinna.” If you have trouble with the technical language of FAO, Jaltemba Jalapeño gives the following graphic description of the leaves:: “Each leaf consists of two leaflets which in turn are divided into two asymmetrical leaflets, looking like butterfly wings. Therefore, each leaf consists of four leaflets.”
As I recall, the leaflets are small, and most Internet sources agree with me. You may find sources that claim that the leaflets are two to four meters or 6.6 to 13 feet long, but this is an obvious error. According to FAO, the length of a leaflet is 2.0 to 3.5 centimeters.
I have never seen this species without leaves, and I tend to think that it is evergreen. However, FAO says: “Leaves are deciduous, but foliage is persistent, as the new leaves appear while the old ones are being shed.”
In defense of its status as an evergreen tree, even the pine loses needles, but not all at once. I think this is a matter of semantics. My definition of a deciduous tree is a tree that periodically loses all its leaves, either because of the approach of winter or some other climatic condition. Note also that FAO does not describe the tree as deciduous, but only the leaves. All leaves are deciduous, sooner or later.
Pithecellobium dulce is a hardy tree. I have seen it growing in fairly dry areas. However, it probably would not do well in a cold climate. Its range is restricted to warm tropical and subtropical regions.
Flowers and Fruit
According to StuartXchange, Pithecellobium dulce has small white flowers that grow in dense heads. Like other members of the family Leguminosae, the fruit is a pod. However, in contrast to the straight or slightly curved pods of peas and beans, the pods of Pithecellobium dulce are contorted in a marvelous fashion. The pods are dehiscent along one of their two edges.
According to Jaltemba Jalapeño, the seeds are black. Around the seeds is an edible pulp that some consider sweet, while others disagree. I myself have never tried it, as far as I can remember. Nevertheless, the taste of the pulp is undoubtedly responsible for the specific name dulce, which means “sweet” in Latin.
I do not recommend experimenting with herbal medicine without expert advice. Above all, pregnant women should never take Pithecellobium dulce internally.
In the Philippines, the leaves are used to treat indigestion. According to “Mga Kahibulongang Pang-ayo sa mga Tanum” by Herminia de Guzman-Ladion, one cup of kamatsili leaves are placed in a pot containing five glassed of water and boiled for ten minutes. Half a teaspoon of salt should be added to the infusion. The dosage for adults is two cups at the beginning, then one cup every four hours. The dosage for children is one cup in the beginning, then a half cup every four hours. Infants take only a teaspoon in the beginning and a teaspoon every four hours.
According to StuartXchange, Pithecellobium dulce is used to treat various other ailments, such as fever and dysentery. Whatever efficacy it may have is due to the presence of such chemicals as triterpene saponins, which have anti-inflammatory properties, and flavonoids, which serve as antioxidants.
“Mga Kahibulongang Pang-ayo sa mga Tanum” by Herminia de Guzman-Ladion
The technical remarks concerning Nahuatl and Latin come from my own knowledge of these languages. Also, all botanical facts for which no citation occurs are derived from my personal knowledge.