Siamese Senna, Kassod Tree
Senna siamea

Family: Fabaceae

What it is like

Also known as Siamese cassia, kassod tree, cassod tree, and Cassia tree. Senna siamea or most commonly known as Siamese Senna is native to South and Southeast Asia that grows up to 18 m in height with an erect and slender stem. It is commonly used as shade tree in plantations, as windbreak, or as hedgerows. The leaves are dark green, alternate, and pinnately compound. The yellow flowers occur at the end of branches. The fruits are black pods with thickened edges. The plant contains Barakol, a compound with sedative and anxiolytic effects, which contributes to its medicinal values. It is used against intestinal worms and scabies. Plant parts such as leaves, pods, and seeds are all edible but has to be thoroughly boiled first prior to eating. Flowers and young fruits are used in curries. The leaves are used as green manure. All plant parts can be used for tanning. The wood is used for joinery, cabinet making, inlaying, handles, sticks, and other decorative uses. In addition, it can be made into charcoal of excellent quality.

Senna siamea is an evergreen Tree growing to 12 m (39ft) by 12 m (39ft) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 9. It can fix Nitrogen. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in very acid soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Height (m): 12

Where it is found

Various types of forests at low elevations. Secondary forest formations on the plains.

Southeast Asia - Myanmar, Thailand, Malaysia, Cambodia, Laos, Vietnam.

Conservation Status: This taxon has not yet been assessed

Countries/locations it is found in

Myanmar; Thailand; Cambodia; Lao People's Democratic Republic; Viet Nam, Africa, Asia, Australia, Benin, Burma, Central Africa, Chad, China, Congo, Côte d'Ivoire, East Africa, East Timor, Ethiopia, Fiji, Ghana, Guinea, Guinée, Guinea-Bissau, Guyana, Hawaii, India, Indochina, Indonesia, Ivory Coast, Kenya, Laos, Malawi, Malaysia, Mali, Mozambique, Niger, Nigeria, Northeastern India, Pacific, Papua New Guinea, Philippines, Sahel, SE Asia, Senegal, Somalia, South Africa, Southern Africa, Sri Lanka, Swaziland, Tanzania, Timor-Leste, Uganda, USA, Vietnam, West Africa, Zambia, Zimbabwe,

How it is used

Food

Rating: 1

The young fruits and leaves are eaten as a vegetable. During preparation the cooking liquid is replaced 3 times to remove toxins. The flowers and young fruits are used in curries.

Medicine

Rating: 1

In traditional medicine, the fruit is used to charm away intestinal worms and to prevent convulsions in children. The heartwood is said to be a laxative, and a decoction is used against scabies.

Laxative: Stimulates bowel movements in a fairly gentle manner.

Parasiticide: Treats external parasites such as ringworm This should perhaps be joined with Parasiticide in

Other

Rating: 4

Agroforestry Uses: The tree is grown to provide shade along roads and in cocoa, coffee and tea plantations. It is also planted as a dense windbreak and shelterbelt. It is pruned into hedgerows and used as a live fence around food crops. When used as a hedgerow, it effectively increases topsoil infiltration, reducing runoff and combating soil erosion. The leaves are used as green manure, and a well-grown tree can yield 500 kg/year of fresh leaves. S. Siamea forms ecto-mycorrhizae and provides very useful mulch, especially in alley-cropping systems. It is used extensively for rehabilitation of degraded land, for example, to re-vegetate aluminium mine tailings. Although not a nitrogen-fixing tree, it has been increasingly used in alley cropping systems, largely because of its coppicing ability and high biomass production. In India, it is used as a host for sandalwood (Santalum spp.), a parasitic tree producing the well-known aromatic wood. Other Uses All parts of the plant can be used for tanning. The concentrations of tannin vary slightly from 17% in the leaves to 9% in the bark and 7% in the fruits. The heartwood is black-brown with paler streaks, sharply demarcated from the 6cm wide band of pale sapwood. The grain is interlocked and occasionally straight; the texture is slightly coarse but even. The wood is medium-weight to heavy, hard to very hard, resistant to termites, strong and durable. It is difficult to work, with a tendency to pick up in planing and it takes a high polish. The dark heartwood, which is often nicely figured, is used for joinery, cabinet making, inlaying, handles, sticks and other decorative uses. The wood has also been used for poles, posts, bridges, mine poles and beams. The dense wood makes good fuel, although it produces some smoke when burning. The energy value of the wood is 22 400 kJ/kg. The wood was formerly preferred for locomotive engines. Its charcoal is also of excellent quality.

Biomass: Provides a large quantity of plant material that can be converted into fuel etc.

Charcoal: Used for fuel, drawing, deodorant, filter, fertilizer etc.

Fencing: Plants that can be used for fencing.

Fodder: Food given to the animals (including plants cut and carried to them) rather than forage for themselves.

Fuel: Usually wood, plant materials that have been mentioned as being a good fuel.

Furniture: A few miscellaneous uses that do not fit easily into other headings.

Hedge: Plants that can be grown as hedges.

Mulch: Used for covering the ground to conserve the nutrients in the soil.

Parasiticide: Kills external body parasites such as hair lice.

Shelterbelt: Wind resistant plants than can be grown to provide shelter in the garden etc.

Soil conditioner: Plants grown to improve the structure of the soil. See also Green manures.

Soil reclamation: Plants that can be grown in such circumstances an the spoil tips of mines in order to restore fertility.

Soil stabilization: Plants that can be grown in places such as sand dunes in order to prevent erosion by wind, water or other agents.

Tannin: An astringent substance obtaied from plants, it is used medicinally, as a dye and mordant, stabilizer in pesticide etc.

Wood: A list of the trees and shrubs that are noted for having useful wood.

Agroforestry Services: Alley crop: Integrates annual crops with rows of perennials.

Agroforestry Services: Crop shade: Plants providing crop shade especially trees.

Agroforestry Services: Nitrogen: Plants that contribute to nitrogen fixation include the legume family – Fabaceae.

Agroforestry Services: Windbreak: Linear plantings of trees and shrubs designed to enhance crop production, protect people and livestock and benefit soil and water conservation.

Fodder: Bank: Fodder banks are plantings of high-quality fodder species. Their goal is to maintain healthy productive animals. They can be utilized all year, but are designed to bridge the forage scarcity of annual dry seasons. Fodder bank plants are usually trees or shrubs, and often legumes. The relatively deep roots of these woody perennials allow them to reach soil nutrients and moisture not available to grasses and herbaceous plants.

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Minor Global Crop: These crops are already grown or traded around the world, but on a smaller scale than the global perennial staple and industrial crops, The annual value of a minor global crop is under $1 billion US. Examples include shea, carob, Brazil nuts and fibers such as ramie and sisal.

Agroforestry Services: Alley crop: Integrates annual crops with rows of perennials.

Agroforestry Services: Crop shade: Plants providing crop shade especially trees.

Agroforestry Services: Nitrogen: Plants that contribute to nitrogen fixation include the legume family – Fabaceae.

Agroforestry Services: Windbreak: Linear plantings of trees and shrubs designed to enhance crop production, protect people and livestock and benefit soil and water conservation.

Fodder: Bank: Fodder banks are plantings of high-quality fodder species. Their goal is to maintain healthy productive animals. They can be utilized all year, but are designed to bridge the forage scarcity of annual dry seasons. Fodder bank plants are usually trees or shrubs, and often legumes. The relatively deep roots of these woody perennials allow them to reach soil nutrients and moisture not available to grasses and herbaceous plants.

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Minor Global Crop: These crops are already grown or traded around the world, but on a smaller scale than the global perennial staple and industrial crops, The annual value of a minor global crop is under $1 billion US. Examples include shea, carob, Brazil nuts and fibers such as ramie and sisal.

Carbon Farming: Plants that can be a critical part of the solution to climate problems. The Carbon Farming Solution - Eric Toensmeier.

Food Forest: Plants for Edible Forest Gardens and Food Forests.

Hedge: Hedge

Nitrogen Fixer: Plants that fix nitrogen in the soil

How it is grown

The tree will grow in a range of climatic conditions, but is particularly suited to the lowland tropics with a monsoon climate, where it can succeed at elevations up to 1,300 metres. It grows in areas where the mean annual rainfall ranges from 500 - 2,800 mm with an optimum of about 1,000 mm. The maximum length of the dry period should not exceed 4 - 8 months. Under semi-arid conditions (rainfall of 500 - 700 mm), it will only grow when its roots have access to groundwater. It requires a mean minimum temperature of 20°c, ranging from 14 - 28°c, and a mean maximum temperature of 31°c, ranging from 24 - 36°c. It is susceptible to cold and frost. Requires a sunny position. It grows best on deep, well-drained, fertile soils, but will succeed on degraded, lateritic soils provided drainage is not impeded. It grows poorly on infertile, poorly drained podzolic soils. It is not tolerant of salinity but is reasonably tolerant of acid soil conditions. It prefers a pH in the range 5.5 - 7.5. Trees grow fast even in comparatively infertile soils. Seedling trees start flowering and fruiting at the age of 2 - 3 years. Once established, they flower precociously and abundantly throughout the year. Planting density varies according to use. In fuel wood plantations, spacing ranges from 1 x 1 metre to 1x 3 metres. In hedges used for alley cropping or as a shelterbelt, spacing between plants in the row should be 25 - 50 cm. Trees respond well to coppicing. For the production of fuel wood and charcoal, plantations are generally pollarded or regenerated by coppice leaving 2-3 shoots/stump after 1 year. It has been reported that sapwood should be removed as soon as possible after felling to prevent insect attack of the heartwood. The root system consists of a few thick roots, growing to considerable depth, and a dense mat of rootlets in the top 10 - 20 cm of soil, which may reach a distance of 7 metres from the stem in 1 year and eventually a distance up to 15 metres. Although many species within the family Fabaceae have a symbiotic relationship with soil bacteria, this species is said to be devoid of such a relationship and therefore does not fix atmospheric nitrogen. Flowering Time: Mid Spring Late Spring/Early Summer. Bloom Color: Pale Yellow Bright Yellow. Spacing: 20-30 ft. (6-9 m).

Propagating it: Seed - requires pre-treatment to soften the hard seedcoat and allow the ingress of water. This can be done by soaking the seed in a small amount of nearly boiling water (which cools down quickly and does not cook the seed) and then soaking the seed for 12 - 24 hours in warm water. Alternatively, a small area of the seed coat can be abraded, being careful not to damage the embryo. Germination of treated seed is about 90% within 60 days. Germination of untreated seeds is about 75% in 4 - 29 days. The seed is usually sown in situ. Seeds should be sown in areas with full sunlight, as the slightest shade reduces germination considerably. Early seedling growth can be quite slow, reaching only 29 cm after 8 weeks of planting. Storage behaviour is orthodox. Viability can be maintained for 3 years in hermetic storage at room temperature with 11-15% mc. There are 35 000-45 000 seeds/kg.

Best place to grow:

Habit: Tree

Hardiness: 9-12

Growth: Fast

Soil: Light (sandy), medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

The sawdust may cause some irritation to the nose, throat and eyes. The wood sometimes produces a yellow powder that may cause irritation to the skin.(Parts of plant are poisonous if ingested)

Its other names

Local names

Ai-coxote, Boordi, Jaha, Jahor, Jeragor, Kasod tree, Kassod, Khee lek, Ki lak yai, Lin pakk kee lek, Maixili, Manje-konne, Phak khee lek, Sebusok, Sia sunaru, Sima tangedu, Thailand shower, akassia, casse du siam, bois pedrix, ironwood, kassod tree, kassod, minjri, muong, siamese cassia, siamese tree senna, wa / aramana, yellow cassia, bombay blackwood.

Synonyms

Cassia arayatensis Naves Cassia arborea Macfad. Cassia florida Vahl Cassia gigantea DC. Cassia siame