Hills And High Rainfall

Indonesian Cassia Needs

Another in a series of articles on spices supplied by the British Govern ment's Tropical Products Institute.

By E. G. BROWN, Colonial Products Laboratory

The main centre of cultivation of Indonesian cassia is the west coast of Sumatra—at Padang (between 1,800 ft and 4,000 ft), in the lower regions of Priaman and Loeboek-Bassoeng, and further south as far as Moera-Laboek and Soengai-penoeh.

The tree from which the cassia bark is derived is cultivated on smallholdings and plantations on steep, often stony, hillsides.

The rainfall in these areas is between 80 and 100 in. a year, with short dry periods in May and September. The bark grown at high altitudes is of a better quality than that grown in the lower regions (below about 3,600 ft).

Although the tree can be pro pagated from cuttings or runners, seed is generally used. Ripe seed from vigorous mature trees, which give a thick bark of good aroma, are chosen. The fruits, about the size of a currant, are attractive to birds and the trees must, therefore, be protected with nets so that good ripe seed may be obtained.

The fruits are usually heaped for two or three days to ferment the pericarp which is then removed by washing; the seeds are dried by sprinkling ashes over them, and they are then ready for planting. Well ripened seed from the tree can be sown directly into the seed-bed, ger minating in five to 15 days, with very few failures.

Rich soil

Seed-beds, 3i ft to 5 ft wide and slightly raised, are prepared well beforehand. Rich soil with water available nearby is preferred, and is deeply dug, stones and roots being removed. The seeds are sown in these beds at 2 in. intervals and covered with i in. of soil.

When two leaves have developed, the seedlings are transplanted 8 in. apart into another bed and here they remain for eight to 12 months, before being transplanted into their permanent positions. The beds are shaded with screens of plaited palm leaves. After five or six months, the

shade can be reduced gradually to accustom the plants to full sunshine.

Although it is customary to transplant year-old seedlings raised in nursery beds, plants are sometimes grown in small bamboo baskets, the whole being planted out when the seedlings are five or six months old.

The best cassia

One authority recommends that the land should be sown with a green manure such as Tephrosia Candida six months before trans plantation. If sown, after the land is cleared, in rows about one yard apart, it will form a thick stand for at least three years, effectively smothering all weeds except climbers.

The young trees are planted in clearings about 2 or 2\ ft in dia meter made in the rows. The Tephrosia, by this time, will have reached a height of 3 to 5 ft, sufficient to provide the plants with the shade they require and also with shelter from strong winds. As the plant requires more light, more Tephrosia can be cut away around it. When the plant is established, the Tephrosia can be cut down to about 6 in. and spread between the rows, to the benefit of the plants.

The best cassia comes from the

trunk, and the bigger the trunk, the thicker and the more valuable the bark. Thick branches yield a bark of lower quality, its value being so low that it barely covers the cost of production. The trees are, therefore, planted closely to encourage the formation of tall straight stems with as few branches as possible.

The best spacing is 3 to 4 yards between plants; a spacing of 3 yards gives most profitable results, but native farmers often plant much more closely, 2 to yards between plants, and then the bark is of lower value.

Harvesting : When the plantation has become too thick for further profitable growth—usually three years after planting, though sometimes sooner—it is thinned.

An early thinning is only neces sary in closely spaced plantations, but shortage of money is frequently the reason for early thinning, although the bark from the first thinnings has very little value.

The first proper harvest is taken two years after the first thinning, when bark of fair quality can be obtained. Subsequently, the planta tions can be thinned annually for 12 to 15 years, by which time all the trees will have been harvested.

In ten years, however, healthy, vigorous trees can attain a circum ference of 3i to 4 ft. Such trees may be left standing for several years, the bark increasing all the time in quantity and thickness.

After the rains

Harvesting takes place at the end of a dry period after the first rains have fallen. The trunk of the tree is first scraped with a small knife, so that cork, mosses, etc., are removed and the bark is exposed.

A horizontal cut, 8 to 12 in. long, is made with a sharp knife about 4i ft above ground level, and, from this, vertical cuts are made down to the foot of the tree.

After loosening the bark a little at the top, it can be pulled off with out much difficulty in strips 2 to 4 in. wide and a yard or more in length. This is repeated round the tree until the lower part of the trunk has been completely stripped.

The tree is then felled, leaving a stump 8 to 12 in. high; the valueless twigs are trimmed off and the bark is removed from the remainder of the trunk and the branches.

The strips of bark are laid out on

mats or wire netting to dry; this is often done under a temporary shelter so that the bark is protected from rain. As the bark dries it curls up into quills, which, after two or three days of strong sunshine, are ready for marketing. If the bark is not dried sufficiently, it is liable to become mouldy and lose its value.

The dried quills are bought by merchants and resold to exporters in Padang. Here the bark is carefully sorted into three grades, “A”, “B” and “C”, according to quill-length, colour, thickness and aroma, and is tied tightly into bundles with rattans; the bundles are then sewn up into jute sacks. They range in weight from 66 lb to 130 lb, bales of 117 lb being usual in the US trade.

Yield varies

The yield is very variable, being dependent on such factors as alti tude, soil, and whether the tree is cultivated or wild; trees of average size yield about 6i lb of stem bark and about half that quantity of branch bark. Over a 10-year period the yield per tree is reckoned to be between 6i lb and 11 lb; trees planted 13 ft apart would give about 1,850 lb per acre.

When the trees are felled, as many as 20 or 30 shoots grow up from the stump and if one or two of these are allowed to grow into new trees, a very fair plantation can be developed in this way. When this is the intention of the grower, the cut surface of the stump is allowed to dry and is then painted with hot tar to prevent rotting.