LAC FROM PALASH

INTRODUCTION :

Lac is the hardened resin secreted by the tiny lac insect. Lac insects thrive only on certain trees called lac hosts. Butea monosperma (Palas), Zizyphus mauritiana (Ber) and Schleichera oleosa (Kusum) are the major lac hosts used in India. The insect starts its life as a larva or nymph which is about 0.6 mm long and 0.25 mm wide across the thorax. The young settles down on a suitable place of the host plant gregariously. On the average some 150 of such larvae may be present per square inch of the twig. They have the typical piercing and sucking mouthparts as in all other Homoptera. A day or two after settlement, the larvae start secreting lac all around the body excepting the rostrum, the brachial plates and tip of the abdomen. Thus it gets encased in a cell of lac which gradually increases in size along with the increase in size of the insect. The insect moults twice before reaching maturity. The duration of each larval inster depends on environmental factors, such as, temperature, humidity, host plant etc. The male larvae produce elongated lac cells while the females produce oval.
After the first moult, the male as well as the female larvae lose their legs, antennae and eyes. After the 3rd moult, the larvae pass on to the so-called pupal stage. During this stage the mouthparts become atrophied in male insects and they stop feeding. The male lac insect may be winged or wingless and they copulate with the females while they are still in encased condition.
During development, the female larvae lose their appendages after the first moult. As the lac insects remain close together, lac secretion from adjacent cells coalesces with each other and forms a continuous encrustation on the tree branch.
Lac culture involves two important steps: (i) inoculation, and (ii) cropping. Inoculation can be carried out through self-infection or artificial infection. In any case the brood lac is necessary. Artificial inoculation is most suitable immediately after crop cutting. In doing so, the brood lac (10 to 30 cm long) are to be tied in bundles of 2 or 3 sticks and in turn they should be tied up to the branches of the host tree. Care should be taken while tieing the bundles so that they have contacts with the branches. The brood lac bundles should be kept on the host tree for 2-3 weeks. If kept longer, ie even after the complete emergence of the lac larvae, there is the danger of a large number of enemy insects emerging from the empty brood lac sticks. Lac crops should be reaped only when mature.
There are four seasons of lac cultivation and according to the Bengali calendar, they have been named as Kartiki, Aghrani, Baisakhi, and Jesthi. The crop period, from inoculation to harvesting, for Kartiki, ranges from July to November, for Aghrani, from July to February, Baisakhi, from November to July, and Jesthi, from February to July. In Nawabganj areas lac is cultivated only once a year, ie Jesthi. In December, after harvesting the plum fruits, Z. jujuba trees are pruned. In January young shoots come up. The brood sticks are tied adjacent to the growing tender branches in the way described earlier. Within a week or two the larvae settle down. Through out the period (February-June) the lac insects secrete a resinous crust on them. In July they are harvested. The branches of Z. jujuba trees are cut into smaller pieces (2 to 4 feet) and tied in bundles. The encrusted lac is then scrapped off the stick and processed in order to get the crude lac.
In the late sixties a Lac Culture Centre was established in Nawabganj which is now almost non-functional. Obviously the lac cultivation is also reduced to its lowest ebb. Most of the locally available lac is of Indian origin. Generally the crude lac is imported, and those locally produced, are extracted in Rajshahi. Lac cultivation involves five major operations which are pruning, inoculation, used up broodlac (phunki) removal, harvesting and lac scraping. Mostly, lac cultivation operations are carried out manually with the aid of locally manufactured traditional tools. Manual lac scraping is a very slow and tedious process. In one method, farmers sit on the ground in a group and scrape lac with the traditional tools like a small scraping knife (dauli) and sickle. In another method, farmers remove lac encrustation by beating lac sticks with bamboo stick. One person scrapes 5-10kg of lac in a day. As scraping is done on the ground, unwanted foreign materials like sand, soil, and wooden twigs find their way into scraped lac, reducing the price to farmers and creating problems during lac processing in industries. In order to increase the output and reduce the drudgery of lac production, a simple power operated roller type lac scraper was designed and developed. The machine consists of a scraper, separation screen, feed hopper, drive mechanism and machine frame. The machine scrapes lac under the action of shear and compressive forces. One person operates the machine and scraps about 13.5kg lac stick in an hour with scraping efficiency of 95 percent.
ECONOMY OF LAC
Approximately 3 million people are engaged in the production of lac in India. On an average, India produces 18 thousand tonnes of lac per year. It is an export-oriented product. Some 80% of the country's total production is exported that earns approximately US$16-22 millions as foreign exchange annually.
The word lac is the English version of Persian and Hindi words that mean “hundred thousand,” indicating the large number of the minute insects required to produce lac. In fact, about 17,000 to 90,000 insects are needed to produce one pound of shellac.
Lac has been used in medicine, dye and resin for over thousand years. India is a leading country in the world for lac production from where 70-80 % requirements of the world are fulfilled.
Lakhera or Lakheri is a community migrated from Marwar or Rajputana in North western India and settled in some areas of Maharashtra. This community has derived it's name Lakhera or Lakheri from Lakh or Lac. They are the makers of the lac bangles and some other articles from lac or lacquer.
Deforested natural forests where large number of wild sapling and trees of lac host trees are available are required to be conserved for regular and fruitful future employment opportunities for coming generation. One can earn about Rs. 39,000 in. the first year on one hectare of land, while this benefit will increase to the Rs. 55,000 in second year. One can get two crops of lac a year, once in the month of June / July and second time in the month of November / December. Each tree producing 5 kg in each crop. Washed and cleaned, the lac sells for Rs 100-Rs 120 per kg in the market.
LAC IN ANCIENT INDIA
In India, lac, lacquer or shellac products have been used from as early as about 1200 B.C as plastic and decorative materials. During the 17th century, after traders had introduced lac dye and, later, shellac to Europe, lac became commercially important there.
The ancient India, red lac and betel leaf juice were used as lipsticks as well as decorative stains for women's palms.
PROBLEMS LAC CULTIVATORS FACE
Lack of adequate processing facilities
The absence of adequate processing facilities, makes lac cultivators unable to realize the full value of their product. This is because the market value of crude lac is rather limited in comparison to the final processed products such as Shellac which commands a premium in the market.
Inefficient extraction method
The lac dye is isolated during the processing and is a valuable product for the textile industry as a colouring agent. The pigment content of the sticklac can be as high as 10% but the yield of isolated lac dye usually is less than 1% due to the inefficient extraction method.