In the “Flowering Plants of TDU” blog series, we look at some of the beautiful flowering plants that dot our serene green campus.
Oroxylum indicum (L.) Kurz
Shyonaka, Bhuta-vriksha, Broken-bones tree Family: Bignoniaceae
Oroxylum indicum is an endangered tree distributed patchily throughout India but present in highest numbers along the Himalayan foothills. Habitat destruction and non-sustainable collection methods coupled with low regeneration and habitat destruction have posed serious threat to the survival and availability of this highly useful tree.
It is a small to medium sized deciduous tree measuring up to 12 m in height. The leaves are oppositely arranged, pinnately compound and one of the largest compound leaves present in trees, measuring 2-4 feet long. Leaflets are triangular-ovate, 5-13 X 3-10 cm. They are clustered at the stem tips. The flowers are borne on long stalks that are raised above the foliage, in clusters. The flowers are bell shaped, purplish yellow, with a rubbery texture. The pods (technically capsules) are long, flat and hang down like swords and measure 40-120 X 5-9 cm. The flat papery seeds which measure 6-7 X 3.5-4 cm have clear wings and resemble the shape of a jet plane. They can glide and float for quite some distance.
Oroxylum indicum is found in tropical and subtropical low altitude open forests in Bhutan, Cambodia, India, Indonesia (Java, Sumatra), Laos, Malaysia, Myanmar, Nepal, Philippines, Thailand, and Vietnam.
The large leaf stalks wither and fall off the tree and collect near the base of the trunk, appearing to look like a pile of broken limb bones. The tree is a night-bloomer and flowers are adapted to natural pollination by bats. They form enormous seed pods that hang down from bare branches. Those long fruits curve downward and resemble the wings of a large bird or dangling sickles or swords in the night.
Oroxylum indicum is assessed in several states, Vulnerable (Andhra Pradesh, Arunachal Pradesh, Assam, Chhattisgarh, Karnataka, Madhya Pradesh and Meghalaya), Endangered (Kerala, Maharashtra, Odisha and Rajasthan.
Oroxylum indicum, also known as Sonapatha is an important herb in Ayurvedic medicine and indigenous medical system for over thousands of years. It has been used as a single drug or as a component of certain poly-herbal drug preparations in Indian system of medicine i.e. Ayurveda. It is the active ingredient of many well-known Ayurvedic formulations like Chyavanprash, Dashmularistha etc. The root bark and stem bark possess anti-allergic properties and are used in treating allergic disease, urticaria, jaundice, asthma, sore throat, laryngitis, hoarseness, gastralgia, diarrhoea, dysentery, infantile, erythema and measles.