Introduction:
Toona ciliata, commonly called too, is one of the foremost and part growing species of the family Meliaceae.
It is a large deciduous tree well known for its timber and fuelwood values and commonly called a toon. It grows best in the small gaps in the forests and also cultivated extensively outside forest areas mainly on farms bund. It has a great market value.
* Occurrences
The tree is found to grow in the sub. Himalayan tract ascending up to about 1.5oom. elevation and valleys of the outer Himalayas from Jammu and Kashmir eastwards in Bihar, plains of Assam, Manipur, Arunachal Pradesh, West Bengal, and eastern and western Ghats and hilly moistened region of the Indian peninsula. In South India, it is mainly confined to evergreen and semi-evergreen forests tree is also distributed in Kerala and Karnataka and moist tracts of Maharashtra and Tamil Nadu.
In its natural habitat, it occurs frequently on moist locations such as ravines, streams banks, or swamps with best growth in deep, rich, moist, Sandy and 100 gm soils and also grows well on the alluvial soils. It prefers good drainage. It is free of sub-tropical climate, where the Normal rainfall ranges from about 1,125 to 4000 mm/gr.
Rainfall occurs during monsoon and winter is mild. Summer is fairly hot and winter is mild.
Absolute maximum shade temperature in its Natural habitat varies from 37.50to 47.5″ and absolute minimum temperature from 1 to 17.5°c. If tended and watered property in the early stage of growth. It has a tendency to grow under dry conditions also. Hence grown extensively as a road ride tree in Northern India having annual rainfall as low as 750 mm. Associated tree species vary with its distribution region.
* Phenology greatly varies from region to region. In northwest India. Tree leaf shedding occurs in December and the tree remains leafless for about two months. New leaves appear towards the end of February and completed in early April. Flowering starts with the advent of spring in March and continues till the end of April or even till may end. Followed by the fruit ripening period in may and Tune In South India, the flowering and trusting periods start one to one and half months earlier
* Reproduction
Natural reproduction takes place through seeds soon after seed fall, seeds and seedlings can be located, – which are washed away during heavy rains. Saplings are often found to establish under the bushes where the density of associated vegetation is less. Good natural regeneration takes place by clearing the associated vegetation in the vicinity of seed bearers. Winged seed escapes at different times till the end of July, covering the ground or some distance around the mother trees.
The seed is collected during the end of May and June from mature (brown colored). Capsules Germination percentage of the seed collected from the ground is comparatively less and thus not much preferred. Ripen seeds are dried in sun for 3 to 4 days and seeds are separated with light strick beating one kilogram of capsules fields about 200 gm of clean seeds. Seed germination percentage ranges from 75 to go percent which varies with altitude or region of its distribution fresh seeds show maximum germination percentage (80 to 94% seed viability pored varies from place to place but in general decreases with Storage time period at room temperature. After three months of storage period seed too viability, reduces (20 to 30%) which continues to decline and cease or become mil after 5 to 6 months of storage seed storing in polythene bags at 10 to 5°C temperature maintains 93% germination after one year and it is recommended to maintain seed viability for a longer period.
Direct sowing can also be practiced seeds are usually sown during June and to August. Toona ciliat cuttings collected during the spring season and treated with IBA (1.0%) + captan (5%) + Sucrose (5%) give the best rooting of 73 percent.
* Plant protection &
Seedlings are sensitive to drought in the nursery stage, hence require shading or mulching with grasses, straw, and leaves seedlings are badly browsed by grazing animals, so fencing is, therefore, necessary for plantation areas. Regular lopping of trees results in large cavities in trees.
Nursery pests are termites, whitefly, Cutworms, and surface grasshoppers. They damage Seedlings by feeding on roots and shoot or cutting them from the soil surface. To control them mix Aldrin 5% dust (20-25kg/ha) with soil while preparing the Nursery beds or 30to 40 gml2 of these insecticides. A spray of Nuvan (1.5 ml) is recommended to control whitefly attacks. Another alternative is to drench the soil in beds polythene bags with Aldrin 30 EC solution (4 to 5mill of water).
Insect Hypsipyla robusta attacks this species during the flowering first-generation attack on inflorescence and flowers and second-generation on seeds, which leads to inhibition of regeneration through seed the insect some time also bore growing shoot causing head back resulting in staggered appearance and this finely affect quality and quantity of timbers. A spray of more than 35 EC respectively on a young plantation in the month of June is recommended. However, it is not possible in the case of an old plantation but the same can be applied in the month of Feb. or March to eradicate the first generation of this insect.
In addition to insect – pest attacks witch’s broom symptom caused by phytoplasma at any age of the tree has been observed in this species. This inhibits flowering and also reduces the growth of the plant. There is no permanent control for this symptom op- except the pruning of the infected branches.
Dr. Yogesh Y. Sumthane, Ph. D., MBA, DM & F, Bamboo Research & Training Centre, Chandrapur
