Family: Fabaceae
Senna siamea (pheasant wood, kassod tree) is a medium sized evergreen tree native to South and Southeast Asia. Traditionally, this plant has been used in herbal medicine to treat typhoid fever, as laxative, to treat abdominal pain, menstrual pain, and reduce blood sugar. It also has fever agroforestry uses. One of which is as a shade tree along roads and cocoa, coffee and tea plantations. It also is used for living fences, as a windbreak tree, and for green manure. It is naturalized in a number of locations globally as well as the island of Oʻahu. Some concerns about this plant include its toxicity to pigs, poultry, horses, dogs and cats, as well as its irritating sawdust. Its long lasting seed bank and ability to form dense stands are also troubling. However, despite its history of naturalization and invasiveness, negative impacts have not been extensively documented to date.
High Risk Traits:
- Thrives in tropical climates
- Broad climate suitability
- Elevation range exceeds 1000 m
- Naturalized in a number of locations, and on the island of Oʻahu
- A potential environmental weed
- A number of Senna species have become invasive
- Allelopathic properties
- Seeds, pods, and foliage are toxic to pigs and non-ruminants
- Sawdust may cause some irritation to the nose, throat and eyes
- Tolerates many soil types
- Reported to form dense thickets in Africa
- Spreads by seeds (human, animal and water mediated)
- Viable seeds pass through guts of animals
- Forms a persistent seed bank
- Coppices vigorously
Low Risk Traits:
- Despite history of naturalization and invasiveness, negative impacts have not been extensively documented to date
- Unarmed (no spines, thorns, or burrs)
- Palatable fodder plant to cattle and other ruminants
- High light demander (may not spread into understory of intact forests)
- Not a nitrogen fixing tree
- Valued as a shade tree
- Pods and seeds are relatively large, which could limit long-distance dispersal
- Herbicides may provide effective control
