Reforestation has been underway in many countries of the region for a very long time. Most of these plantations were established to produce timber and a number of these plantation areas can now be seen as extremely successful, while others have been less so. But what constitutes "success" and "failure"?
A nursery for seedlings... methodologies for raising seedlings of different species can differ substantially and extensive research may be needed to develop appropriate methods when new species are introduced into reforestation programmes.
Successful past plantation forestry practices and initiatives
Notwithstanding the comments above about "miracle" trees, one of the undoubted successes of the past has been the identification and widespread adoption of certain key species that were able to tolerate some of the more infertile soils present at many of the degraded sites available for reforestation across the region.
But it must also be emphasized that a significant portion of plantations are on longer rotations for production of high quality hardwoods (e.g. teak, mahogany and dipterocarps), and softwoods (e.g. Pinus spp., Araucaria, Dacrydium etc. for plywood, veneer, framing and similar uses).
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Box 1. Some definitions Reforestation: to re-establish trees on land previously occupied by forests. This is a broad term covering many kinds of planting, including industrial monocultures as well as multi-species planting programmes. Restoration: to re-establish the presumed structure, productivity and species diversity of the forest originally present at a site. In time, the ecological processes and functions of the restored forest will match those of the original forest. Rehabilitation: to re-establish the productivity and some, but not necessarily all, of the original plant and animal species diversity once present at a site. For economic or ecological reasons, the new forest may contain some species not originally present at the site. In time, the protective function and many of the ecological services once provided by the original forest may become re-established. Monoculture: a plantation occupied by a single tree species. |
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Box 2. Reforestation successes in Asia and the Pacific using particular species Case Study: Viet Nam One striking success has been the widespread establishment of the bamboo species, Dendrocalamus membranaceus. This species was once found in only one or two provinces, but is now planted more widely in many provinces and covers some 80,000 ha. Success can be attributed to developing an efficient method for reproducing planting material by air layering of branches rather than using rhizomes. Harvesting can be done after three years and there is a ready market for the product. Another success has been the use of Casuarina equisetifolia in sandy coastal areas. The species tolerates the harsh site conditions extremely well. Over 100,000 ha have been planted successfully using this species. Case Study: Indonesia A significant success story in Indonesia has been the widespread adoption by farmers in Java of Paraserianthes falcataria (picture below) and Acacia auriculiformis for use as cash crops and "green banks".
The value of these small rural woodlots has led to the development of local seedling vendors and the creation of processing industries to use the timbers. The reason for the success was that there was an appropriate silvicultural technology to raise seedlings and a ready local market for the product. Success has also been achieved in some areas of South Sulawesi growing Pinus merkusii for resin production. |
Nursery systems have been developed to allow large-scale seedling production of these species and field establishment and weed control practices have been refined to allow reliable and successful plantation establishment to occur (Evans and Turnbull 2004, Nambiar and Brown 1997, Cossalter and Pye Smith 2003).
These approaches have often led to the establishment of high-yielding timber plantations. Large plantations of some of these species have now been established in many countries across the region. These successes have led to the development of improved techniques for local seed collection, seed storage and efficient methods of plantation management in a number of countries.
Most countries now have a number of technically-skilled reforestation practitioners. Such technical skills will be useful for any kind of future reforestation, irrespective of the species used or the types of plantations that are established.
Some provenance testing of these species has also been carried out. Localised tree breeding based on promising trees and stands has also occurred. As further genetic research is undertaken, the yields from these various plantations are likely to increase.
There is no question, therefore, that many of these plantations have fulfilled the particular objectives of those who established them and should, in that sense, be regarded as "successes".
The poor growth of trees... this is largely due to insufficient weed control during the early stage of plantation development. Without such weed removal, the trees will be out-competed.
Less successful past plantation forestry practices and initiatives
But there have also been numerous "failures".
Although it is probably impossible to determine the ratio of successes to failures, some of the more obvious failures - where trees have all died or stagnated - have occurred for technical reasons.
Among these factors are lack of weed control, inappropriate species or provenance choices, inadequate nutrition, poor planting stock or failures because of droughts or fires. Such problems should become less frequent as the numbers of trained staff increase, and established reforestation methodologies become more widely adopted.
