Karvi

Appearance

It is a large shrub, sometimes attaining 6–20 ft in height and 21⁄2 inches in diameter and flowers between July and September but what makes it most famous is that it takes nearly a decade for the bloom cycle to happen. Its leaves are home to several insects including caterpillars and snails which feed on it. The shrub has an interesting life cycle, it comes alive green every year with the coming of Monsoon, but once the rainy season is over, all that is left is dry and dead-looking stems. This pattern repeats itself for seven years, but in the eighth year the plant bursts into mass flowering.

Plants that bloom at long intervals like "Strobilanthes callosus" are known as plietesials, the term plietesial has been used in reference to perennial "monocarpic" plants “of the kind most often met with in the "Strobilanthinae"” that usually grow gregariously, flower simultaneously following a long interval, set seed, and die. Other commonly used expressions or terms which apply to part or all of the plietesial life history include gregarious flowering, mast seeding, and supra-annual synchronized semelparity.

In 1953 Sharfuddin Khan describing the plant in the former Hyderabad State wrote:

Botanical Name - Strobilanthes callosus

Strobilanthes, Blume.; F.B.I. IV-429. S. callosus, Nees.; F.B.I. IV-451. Brandi's Ind. Trees, 500. Gamble's Ind. Timbers, 518. Vern. Karvi, Mar.

A large shrub, sometimes attaining 6-20 ft. in height and 21⁄2 inches in diameter; branches often warted or scabrous-tubercled. Leaves opposite, 7 by 3 in., sometimes much larger, crenate, rough, conspicuously marked with five lines above, nerves 8-16 pair; petiole 2-3 in. Flowers in strobiliform spikes 1-4 in. long, often densely or laxly cymose; bracts 1/2 - 1 in. long, orbicular or elliptic. Calyx 1/2 in., in fruit often exceeding 3/4 in., sub-equally 5-lobed to the base; segments oblong, obtuse, softly hairy. Corolla tubular-ventricose, 11⁄2 in., glabrous without, very hairy within, deep blue; lobes 5, nearly equal, contorted in bud. Stamens 4; filaments hairy downwards; anthers blunt; not spurred at the base. Ovary 4-ovuled; style linear; stigma of one long linear-lanceolate branch the other minute. Capsule 3/4 by 1/3 in., seeds more than 1/3 in. long, thin, obovate, acute, densely shaggy with white inelastic adpressed hair, except on the large oblong areoles.

Tolerably common on the Kannad and Ajanta ghats in Aurangabad. In 'List of Trees, Shrubs, etc., of the Bombay Presidency,' Talbot remarks. "It covers large areas on the Konkan and N. Kanara ghats, and forms the undergrowth in many of the deciduous moist forests. Sometimes a very large shrub. A general flowering takes place every seven or eight years. The white glabrous bracts become covered, after the flowering is over, with viscous strongly smelling hairs. The flowers vary in colour from purple-blue to pink. A general flowering of this species in N. Kanara, took place in Sept-Oct. 1887. The capsules ripen during the cold and hot seasons, and are elastically dehiscent, making a paculiar, almost continuous, niose during the shedding of the seeds in a forest of this species".— Sharfuddin Khan, M. D. "Forest flora of Hyderabad State. AP Forest Division, India; 1953."

In 1956 during the Reorganisation of the Indian States based along linguist lines, the above-mentioned state of Hyderabad was split up between Andhra Pradesh, Bombay state and Karnataka.

Distribution

"Strobilanthes callosus" which is mostly peculiar to the hills of the Western Ghats in India can be seen growing wild around Mumbai, Tansa, Khandala, Bhimashankar, Malshej Ghat, Basgadh, Anjaneri, Dhodap, Salher-Mulher, Mulshi, Aurangabad, Konkan etc. in the state of Maharashtra, parts of the state of Madhya Pradesh, parts of the state of Gujarat and in large areas of and Uttara Kannada Ghats in the state of Karnataka among other places all along the Western Ghat hills on the west coast of India.

Defense

Some species of "Strobilanthes" including this one are examples of a mass seeding phenomenon termed as masting which can be defined as "synchronous production of seed at long intervals by a population of plants", strict masting only occurs in species that are monocarpic -- individuals of the species only reproduce once during their lifetime, then die.

Uses

While the leaves of "Strobilanthes callosus" are poisonous, toxic and unfit for human consumption it is used as a traditional medicine herb by the local adivasi tribals and villagers for the treatment of inflammatory disorders. Its leaves are crushed and the juice obtained is believed to be a sure cure for stomach ailments.

The plant has been the subject of scientific research which confirms its use in folk medicine as a valid anti-inflammatory and antimicrobial herbal drug with anti-rheumatic activity.

Related species include "Strobilanthes cusia" BREMEK, used in Chinese and Japanese herbal medicine, and "Strobilanthes forrestii" Diels, used in Chinese herbal medicine."Strobilanthes callosus" has sturdy stems which along with its leaves is generally used by the local adivasi tribals and villagers as thatching material to build their huts.

Immediately after its mass flowering the Karvi honey collected by wild bee honey hunters is a popular local delicacy, it is much thicker and darker than other varieties."