Species Selection in Commercial Forestry

Presented by

Tharani Dilshara

Selection of species is important in starting a plantation project because the species selected decides the affected silvicultural practice and the management and utilisation of crops.

Selection of a tree crop for planting depends on the purpose, the species potentially available for planting, site qualities, silvicultural and economic factors. Before considering the site characteristics and demands, it is essential to have clear understanding of the objectives of raising the particular plantations and those factors will narrow the choice of a species. Species selection in commercial forestry is mainly determined, however, by the demand and establishment costs.

As a rule, where a native species meets the need there is no reason to choose an alternative because of the conservation purposes more prefer the native species. However, the majority of successful plantation in the tropics consist exotic species.

Species and provenance trials have to be carried out before establishment of plantations using new species. Site qualities play a major role in the interactions between genotype and environment. Site quality factors such as climate, soil, physiographic and biotic factors affect the growth at different manner even for the same species. Another major determinant of species selection is the specific silvicultural requirement of the tree species. Having matched species to the site, a further vital decision is selection of the most suitable provenance.

In Sri Lanka the main plantation species are Teak, Eucalyptus (Eucalyptus grandis) and Mahogany. Most of the fuel wood, miscellaneous hardwood and teak plantations are located in the dry zone, Eucalypts and Pine plantations are mostly in the up country wet zone and Mahogany plantations are situated in intermediate and wet zone.

Timber and Non-timber Forest Products Manufacturing and Marketing

Presented by

Yasika Subasinghe

The new forest policy of Sri Lanka includes provisions for the production of timber and NTFPs, value addition and marketing. Greater responsibility is given to local people, cooperatives, other organised groups or private bodies in commercial forest production for industrial manufacturing and marketing

According to the Central Bank of Sri Lanka, the population in Sri Lanka is still growing at a rate of 1.1%. Annual sawn-wood consumption per 1000 persons in 1993 was estimated to be 31 m³ and sawn-wood demand is projected to grow from 0.544 million m³ in 1993 to 0.885 million m³ in 2020, at a rate of 12,600 m³ per year. Demand for plywood and other wood-based panels are predicted to increase at rates of 2.8% and 3.5% respectively per year. Even though natural forests and forest plantations have the potential to supply country’s total timber demand, most of this is either in inaccessible protected area or felling is banned. Therefore, around 70% of the industrial timber have to be supplied from home gardens, rubber and coconut plantations, and trees planted along farm boundaries, on roadsides, and in urban areas.

Timber manufacturing process comprises of log sorting and barking, log sawing or breakdown, sorting and grading, drying, re-grading and surfacing. At each stage traditional knowledge in timber use and modern technology in maximization of the timber yield should be coupled together. Promoting local tree species in timber manufacturing and marketing can also be recommended.

Non timber forest products play a major role in income generation of local peripheral communities in natural forests. Under policy on wood and NTFP’s industries and marketing, a greater responsibility will be given to the local people, organized groups, cooperatives, industries and other private bodies in commercial forest production for industrial manufacturing and marketing. Efficient forest products utilization, development of competitive forest industries based on sustainable wood sources and manufacturing of value-added forest products will be promoted. Effective measures to protect the forests and prevent illegal trade in wood, NTFPs and endangered species of flora and fauna will also be instituted.

There are many non-timber forests products extracted from natural forests in Sri Lanka. Some of them are gums, resins and oleoresins, barks, leaves, flowers, fruits and seeds, flowers and their juices, leaves, grasses, bamboos, canes and creepers, Kitul (Caryota urens) products, edible plants and  medicinal plants.

When a timber product or non-timber forest product is to be manufactured or extracted the market potential for that particular product should be identified at prior stages of planning. Timber manufacturers in both government and private sectors adopt different methods of marketing their products such as holding auctions, facilitating loans for furniture, publishing in websites, paper advertisements. Considering local non timber forest products collectors there is no so called marketing procedures but sometimes intermediate buyers tend to use websites and newspaper advertisements for marketing purpose. However better techniques in yield optimization of timber and sustainable extraction of non-timber forest products should be given more consideration in achieving policy objectives.

Pruning and Thinning Practices in Commercial Forestry

Presented by

Chirosha Lakmini

In commercial Forest Plantation cycle, after land preparations and planting of seedlings, pruning and thinning are conducted to obtain better quality timber. Pruning is the removal of live and dead branches from the bole at early stage. Pruning can be natural or artificial and natural pruning is further divided into physical and biotic processes. Trees do not always benefit from pruning and therefore it should only be carried out after careful consideration of the objectives of management. 

Generally pruning practice has three steps, (i) to remove dead, broken, diseased branches; (ii) to identify main stem and remove competing branches; and (iii) to suppress or removal of lover limbs. Pruning types are singling, formative pruning, brashing and high pruning. Yet there are special pruning types for Conifers which are variable lift and fixed lift. The equipments used in pruning are the head pole saw, the pole pruner, bypass style hand sheer, foot handles, hand saw.

Thinning is the felling made in an immature stand for the purpose of improving the growth and form of the trees that remain without permanently breaking the canopy. Selection and systematic are the two main thinning types. Selection thinning can be further divided into low thinning, crown thinning and systematic thinning is the row thinning. A good thinning requires a clear objective, a sharp axe and a cold heart. Objectives of thinning, however, vary with the growth potential and increase of net yield. Thinning type, intensity, thinning cycle and distribution of remaining trees are the main concerns in thinning practices.