Shorea robusta or Sal tree is a large, deciduous tree found in India, Myanmar and Nepal. It is a medicinal tree and used in Ayurveda for thousands of years to treat variety of diseases including piles, leucorrhoea, gonorrhea, skin disorders, ulcers, wounds, diarrhea, dysentery, burning sensation, seminal weakness etc.
The resin obtained from the tree is known as Sal damar, Bengal Dammar, Laldhuna Ral, Rhal or Dhoom. It has carminative, stomachic and astringent properties. It gives relief in skin disorders, pain in nerves, burn injury, fever, enlargement of spleen, abnormal discharge from body (menorrhagia, leucorrhoea), diarrhea, and bleeding piles. It is also given in gonorrhea and for weak digestion. In Siddha, it is suggested for ulcers, wounds and menopausal disorders.
Sal is a deciduous tree with a dark brown bark.
Leaves are simple, alternate, 10—30 cm long, 5—18 cm broad, ovate-oblong, acuminate, tough, thinly coriaceous, glabrous and shining when mature, cordate or rounded, lateral nerves 12—15 pairs, petioles 12—2 cm long, stipules 7.5 mm long, pubescent and deciduous.
Flowers are regular, bisexual. Axillary racemose panicles 7.5—23 cm long. Petals are 5, narrow-oblong or lanceolate, silky tomentose outside. Calyx-tube is very short (not enlarged in the fruit) adnate to the torus, lobes 2.5 mm long, ovate, grey tomentose outside, imbricate, unequally enlarged in the fruit and closely embracing it.Stamens are numerous, shorter than petals, connectives withsubulate bearded appendages, minutely 3-fid at apex; ovary superior, 3-locular with two ovules in each loculus, style subulate. Fruits are ovoid.
The botanical name of Shal is Shorea robusta. It belongs to plant family Dipterocarpaceae. Below is given taxonomical classification of plant.
- Kingdom: Plantae – Plants
- Subkingdom: Tracheobionta – Vascular plants
- Super division: Spermatophyta – Seed plants
- Division: Magnoliophyta – Flowering plants
- Class: Magnoliopsida – Dicotyledons
- Subclass: Dilleniidae
- Order: Theales
- Family: Dipterocarpaceae – Meranti family
- Genus: Shorea Roxb. ex C.F. Gaertn. – shorea P
- Species: Shorea robusta C.F. Gaertn. – sal tree P
Nativity: Indian Subcontinent
Part(s) used for medicinal purpose: Resin exuded from the tree, Heartwood, flowers
Plant type: Large tree
Distribution: Grows in the jungles of tropical Himalaya, Assam, Khasia Hills and Central India, up to 1700m.
Habitat: Dense moist deciduous forests, on hill slopes and flat grounds where the soil is deep
Flowering & Fruiting: March – April
Economic Importance: Timber tree. Its wood is strong, durable and resistant to fire. It is used for housebuilding, telephone and electrical poles, sleepers and boats, and for furniture and other carpentry works.
- Resin is used in paints and varnishes, and for sealing the joints or seams in boats.
- Oil obtained from resin is known as Chua oil. It is used for ear troubles and skin diseases.
- Leaves are widely used for making leaf plates and cups.
- Seed oil is used locally for lightening and cooking.
Vernacular names /Synonyms
Latin name: Shorea robusta
Sanskrit: Agnivallabha, Ashvakarna, Ashvakarnika, Chiraparna, Dhanya, Dirghaparna, Dirghashaka, Divyasara, Jaladashara, Jaranadruma, Kaushikahva, Kushika, Lalana, Latashankha, Latataru, Rala, Ralakarya, Sala, Salaniryas, Salaveshta, Sarja, Sarjakarya, Sarjarasa, Sarjjaka, Sasyasambara, Sasyasamvera, Shankataru, Shankurriksha, Shasyasambara, Shura. Sidhaka, Sureshtaka, Tarkshyapravasa, Vallivriksha, Vansha, Vastakarna, Yakshadhupa
English: Indian Dammer (Oleoresin), Sal tree
Hindi: Sakher, Sakhu. Sakhua, Sakob, Sal, Sala, Salwa, Shal, Swet Dhuna (Ral, Shal, Resin)
Tamil: Attam, Kungiliyam, Shalam
Unani: Raal (resin)
Constituents of Shorea robusta
Heartwood contains a chalcone, glycoside 4’hydroxychalcone- a’ -O-beta-D-glucopyranoside, apolyphenol-hopeaphenol, leucoanthocyanidin.
Bark contains ursonic acid and oleanane, Shoreaphenol.
Oleoresin, contains triterpenoids, the derivatives of ursonic, oleanane and a triterpene acid.
Ayurvedic Properties and Action
Sal is astringent, bitter, sweet in taste (Rasa), pungent after digestion (Vipaka), and is cool in effect (Virya). It is a Sheet Virya herb. Sheet Virya or Cool potency herb, subdues Pitta (Bile) Vata (Wind) and increases Kapha (Mucus). Sheet Virya herb gives nourishment to body and steadiness. It supports building of body fluids.
Rasa (taste on tongue): Kashaya (Astringent), Madhura (Sweet)
- Guna (Pharmacological Action): Ruksha (Dry), Ushna (Heating)
- Virya (Action): Shita (Cooling)
- Vipaka (transformed state after digestion): Katu (Pungent)
Important Medicinal Properties
The resin obtained from the tree is stomachic, astringent, antidysenteric, styptic, antiseptic, and antigonorrhoeic. The bark and leaves are cooling, astringent, acrid, anthelmintic, pain-relieving, constipating, urinary astringent, tonic and purifying.
- Analgesic (resin): Acting to relieve pain.
- Antipyretic (resin): Effective against fever.
- Anti–inflammatory (leaves decoction): Reducing inflammation by acting on body mechanisms.
- Antinociceptive (leaves): Inhibits nociception, the sensation of pain
- Antibacterial (flower decoction):
- Anti–Obesity (leaves): Reduces obesity
- Antiulcer (resin): Tending to prevent or heal ulcers.
- Immunomodulatory (bark): Modifies the immune response or the functioning of the immune system.
- Wound healing: Heals the wound.
Dosage of Shorea robusta
- Powder 3-5 grams
- Decoction 50-100 ml
- Gum-resin 1-3 grams
- The resin exuded from the tree is used for dysentery, weak digestion, gonorrhea and as an aphrodisiac.
- For Asthmatic attacks, cough, fumes of gum-resin are inhaled.
- For burn injury, in one liter Sesame oil, 250 grams of Ral / resin is heated for 20 minutes. This is made into fine paste by grinding. This paste is applied on affected body part, 4-5 times a day for one to two weeks.
- In Bloody diarrhea, bleeding piles, urethral discharges gum-resin is taken internally.
- On ulcers, infected wounds and skin eruptions, the gum-resin is applied.
- In leucorrhoea and metrorrhagia, heartwood powder / gum resin, is given.
- For polyuria, emaciation, anemia due to loss of blood, goiter and diseases due to vitiated blood, the powdered flowers or heartwood is used.
- For typhoid, the bark of tea is prepared like tea and taken orally for five days.
- In leucorrhoea, 1g resin per day for 30 days gives significant relief.