A medium-sized, occasionally large deciduous tree with a milky sap. Leaves alternate, 10-25 cm long, elliptical, pointed, rather leathery. Male and female flowers in separate spherical heads. Fruits 5-10 cm in diameter, irregularly lobed. Good illustrations of the fruits can be seen in Panday (1982) and Storrs and Storrs (1984). One of the most valued fodder trees in Nepal.
A deciduous tree, which drops its leaves for a short time at the beginning of the hot season. Young trees will withstand moderate shade, but older trees grow best in full light. It grows best on deep permeable soils with a good supply of moisture, and does not thrive on poorer sites. Young seedlings are badly damaged by frost, and the tree should not be planted in frosty areas. At modemtely high altitudes many seedlings turn yellow in the cold period, and some die back; some of the seedlings which have died back will, however, eventually recover (Mulder, pers. comm.). Young plants are very liable to damage by browsing animals.
It is found from the Terai to about 1300 m, occasionally to 1600 m in isolated, well-protected spots. In its wild state it often grows along the banks of streams. Its range has been considerably extended by planting. Rather strangely no authenticated herbarium specimens have been collected from Nepal and hence it is not included in the Enumeration (Ham et al., 1982). Outside Nepal it extends westward to Kumaon in the Himalayan foothills, and it is also found in southern India, Sri Lanka, Burma and Malaysia.
The fruits are greedily eaten by birds and monkeys, which scatter the seeds under the trees, where, after the rains, numerous seedlings may be found. (This assumes the fruits have not been previously gathered for human consumption.) Exposed seed usually does not germinate, and it is better if the seed becomes buried. Unless they are in moist and fairly shady conditions many seedlings die in the dry season.
The fruit ripens between late June and early August in most localities, but there are considerable variations; local checks are advisable. When ripe the fruits begin to turn yellowish. As the trees are lopped for fodder, and the fruit has a market value, it is usually necessary to buy or rent trees to assure a supply of seed. As a rough guide one tree will yield about 80 kg of fruit and about 6000 seeds (Tengnas, 1981). It is also possible to buy fruit in the market but some caution is needed, as the seed loses its viability rapidly. The seed from fruit which is collected green and stored to ripen is also of low viability. Seed is sometimes more easily obtained in the Terai than in the hills, and in the Pokhara area it is frequently brought up from the Terai. There is some risk, however, of bringing in less well-adapted provenances if this method is used.
The seed is recalcitrant, losing its viability within a few days; it should be sown as soon as possible, and not more than two days after collection. It if has to be kept for a day or two it should be kept in the fruit until it can be sown. There are from 1900 to 5000 seeds kg-1; 18-25 fruits weigh 1 kg and there are 10-30 seeds in each fruit. The flesh should be removed from the seeds immediately before they are sown. At lower altitudes germination usually begins about two weeks after sowing, and is complete 1-2 weeks later; above 1500 m it may take longer. Fresh seed has a germination percentage of about 80. It should be possible to raise between 1000 and 2000 plants from 1 kg of seed.
Large polypots, 4 inch x 7 inch (10 cm x 18 cm) lay-flat should be used, with 20-25 per cent compost added to the potting mixture. The seed may be sown directly into the pots, at two seeds per pot; if more than one seed per pot germinates the surplus seedlings may be pricked out into another pot, or otherwise thrown away. The seeds should be covered with about 3 mm of soil, or a mulch. An alternative method is to sow the seed at the rate of 1 kg m-2 in raised beds; the seedlings should be pricked out when they are about 5 cm tall, 3-4 weeks later.
The short viability of the seed dictates the sowing date, just before the onset of the monsoon. This will produce plantable seedlings, which should be 20-25 cm tall or more, by the next monsoon. The seedlings are fairly robust, and two or three weeks after the seed has germinated, shade against sun and rain is no longer needed; however protection from frost is necessary where this is a hazard. The seed and young seedlings also need protection against rodents. A strong orange-coloured taproot is developed and frequent root pruning is necessary. This should begin in September or October, depending on growth. It is not necessary in winter, but should begin again in March, and repeated at least once a month, until the seedlings are planted out; during periods of rapid growth more frequent root pruning may be needed. Seedlings should be spaced out with 5-10 cm between the rows not later than March or April. Regular watering, once a day, preferably in the evening, is needed. In nurseries at higher altitudes the leaves may become yellow and the shoots die back during cold weather.
Stumps are reported to have been successful, but no details are available (Mader and Stewart, 1983). Root cuttings approximately 5 cm long from the taproots of nursery seedlings have also succeeded (Mader and Stewart, 1983; Tengnas, 1981). According to G.B. Rimal (1984) best results are obtained from root cuttings taken in Chaitra (March-April). Early attempts to root stem cuttings were largely unsuccessful (Napier, 1988; Sharpe, 1984c; Tyystjarvi, 1981), but later, at Hetauda, A.V. Parajuli (1988) succeeded in rooting 46 per cent of cuttings taken in March, and 31 per cent in February. Best results were from cuttings 20 cm long, with at least three buds, taken from the lower part of the stems of 1.5-year-old seedlings.
This is a tree which needs a good deal of care and attention. As it is likely to be used mainly by individual farmers planting a few trees on their farms, more elaborate methods of planting and maintenance than those used for routine plantations may be justified. Neville (1987c) compared the use of pits 1 m x 1 m x 1 m, with the normal 30 cm x 30 cm x 30 cm pits, in Dolakha District at 1360 m. After two years, in the normal pits survival was 44 per cent and mean height 15 em, compared with 85 percent survival and a height growth of 30 cm in the larger pits. Certainly this is an improvement, but a height of 30 cm in two years is not very good. However at Chirtungdhara (800 m) after 16 months there were no significant differences in height and survival between plants (a) without fertilizer, (b) with 25 g complexol per plant, and (c) with added compost; survival ranged from 87 to 93 per cent, and mean heights from 60 to 65 cm. These results are not very conclusive, but continued trials of simple methods usable by farmers would be useful. For plants near their·houses they might even be prepared to water them from time to time.
Growth in early years is rather slow, and decreases with the altitude. One of the best results was at Hetauda, where plants 18 months old averaged 1.6 m in height, on ground which had been weeded and thoroughly cultivated to a depth of 20-25 cm, and to which 20:20:0 fertilizer had been added at the rate of 400 kg ha-1. These are near to optimum conditions. Elsewhere height growth at two years old ranges from about 1.1 m in the Terai to 30-60 cm at 1500 m. Above 1500 m, and in exposed places above 1300 m, growth is very poor. Later growth is faster. Timber specimens in India indicated a mean annual diameter increment of 13-17 mm, which is comparatively quick.
Its main value in Nepal is for fodder. Farmers prize it for its high nutritive value and good yield of leaves. They have a crude protein content of about 16 per cent, and are relatively low in tannins. The main collecting season varies with the locality. In Bara District in the Terai the most important season is during the monsoon, followed by mid-December to mid-February, and the pre-monsoon period from mid-April to mid-June (Upadhyay, 1991). Near Dhankuta it is fed between mid-October and mid-January (Dutt, 1992). In Lamjung District midSeptember to mid-November is the important period (K.P. Gajurel et al., 1987). (The leaves fall between February and April, and the new flush is in the pre-monsoon period.) There are no adverse effects on animals' health at any time in the year. The tree can be lopped for fodder after it is about four years old. Panday (1982) describes a tree over 30 m high by 3 m in girth which was still giving a good yield of fodder after more than a hundred years of leaf harvesting. It was owned by four families.
Estimates of fodder yields vary considerably. Some are not very reliable, being based largely on farmers' estimate. One result based on measurements is from Kaski District where five trees with heights ranging from 10.6 to 23 m, average 14.7 m, and diameters from 22 to 72 cm, average 38 em, produced yields of 36 to 270 kg of fresh matter, average 128 kg (Vaidya and Gautam, 1989). Sometimes the leaves of young trees are removed individually by hand, and branches are not lopped; this is partly because the small lateral branches are strong enough to bear the weight of a man climbing the tree (Panday, 1982).
The fruit is edible by humans, and is sold in local markets; a pickle is made from the young fruit, and in India the young male flower heads are also pickled (Gamble, 1922). The wood is hard, with a white perishable sapwood and a yellow heartwood which turns dark brown and is termite resistant. It weighs about 640 kg m-3. In India it is a valuable timber, but in Nepal because the tree is so highly valued for fodder and fruit its timber is not much used.
In many parts of Nepal it is the fodder species most preferred by farmers. It is not, however, generally the most used, partly because other trees are commoner, partly because it is not a very easy tree to grow. Nevertheless it is in great demand for planting by farmers. Survival rates in farmers' plantations are very variable, ranging from 15 per cent after four years in the IHDP area to about 60 per cent after one year in the Community Forestry Development Project (J.G. Campbell and Bhattarai, 1983). There is thus room for considerable improvement, but if this can be achieved A. lakoocha is a most valuable tree for Nepal. Because it requires fertile soils for good growth, and also quite a lot of care and attention, it is more suitable for planting by individual farmers than in community plantations.