2. SELECTION: starting with appropriate material
In any tree planting endeavour, it is essential to start with the right reproductive material. Your efforts to collect, analyse, store, propagate or improve plants will be wasted if you start with wrong or inferior material. Unfortunately, there are examples worldwide of forest regeneration programmes that have not been a success, because inadequate attention was given to starting with the right material.
This section will help you ensure that you know what background information you may need to lay a firm foundation. There are four aspects.
First, you should understand the technical, social, economic and environmental context in which trees will be regenerated.
Second, once the context is clear, it is important to know what the future uses of the trees or forests will be.
Third - knowing this - you will then be in a position to begin deciding which are the most appropriate species and geographic sources (or provenances) of reproductive material that you need.
Fourth and finally, the choice of material type can then be made, whether it is to be seed (as will often be the case), cuttings or some other more specialised material.
These four aspects are considered in the following topics.
The context of your work will determine (i) the scope, depth and background of information that you or your colleagues will need, and (ii) how you should design your project or programme. The context can be technical, socioeconomic or environmental/geographic.
Species and provenance trials - if you do not know which species or sources are the most appropriate, and are concerned with obtaining material for testing in field trials, then you will need small quantities of material, certified to high physical and genetical quality, propagated and planted under strict conditions. It will be important to find a reputable supplier, and to have expertise in the principles and practice of applied research and field trials. You will have to be particularly vigilant about the potential problems of introduced species.
Genetic improvement - if the material is to be used in a programme of genetic improvement, then you should already be clear about the species and provenances (sources) required, and will probably be producing your own reproductive material. The material will be raised, bred and propagated under strict conditions. It will be essential to have good expertise in genetics and propagation, and to understand the potential costs and benefits of breeding, including advanced techniques such as genetic engineering.
Natural forest management - management of natural forests is mainly concerned with optimising the natural seeding and regeneration of the desired species. In this context, knowledge of the species reproductive biology will be important. Only in cases of direct seeding or enrichment planting will seed need to be collected and raised as plants. Good silvicultural knowledge and practical expertise will be important.
Commercial plantations - assuming that species and provenances have been appropriately identified for large scale planting, then key factors will be to ensure an adequate quantity and quality of reproductive material, at an appropriate cost. Efficient and effective handling and propagation of large quantities of material in large scale nurseries will be important.
Conservation of genetic diversity - the role of reproductive material will depend on whether conservation is to be in situ or ex situ. Knowledge of ecological, silvicultural, genetic, botanical and taxonomic sciences will be important, as well as experience of how to apply this in the field.
Biological / taxonomic studies and exploration - reproductive material (flowers, fruit, seeds, and pollen) play a key role in identifying species and understanding their evolutionary history. Very small quantities are involved, and the material does not have to be viable. Good botanical and taxonomic knowledge will be important.
Watershed management - besides planting activities associated with soil conservation, there may be a demand for vegetative reproductive material to support bio-engineering works. Land-use, agricultural and forestry experience will all be needed.
National development - Forestry programmes may play an important role in national development. If such cases, adequate reproductive material will be an important key to success. Attention may need to be paid to the institutional context, and capacity building may be required. This is often a justification for projects to establish national tree seed centres.
Community forestry - (or social, collaborative, or participatory forestry) will provide excellent opportunities for involving local communities in all aspects of supplying seeds or other material, and of directly benefiting from the many goods and services that forests provide. Collection of material and propagation techniques will need to be straightforward, and consideration given to decentralisation of activities, such as establishment of nurseries. Participatory approaches and indigenous knowledge will be particularly important.
Urban forestry - this specialised activity may require a high diversity of forest reproductive material to meet amenity and aesthetic objectives. Species may need to be adapted to a wide range of conditions, and material obtained from many different sources and suppliers. Arboricultural expertise will be important.
Agroforestry - activities concerned with selection, handling and propagating reproductive material will probably be closely linked with agricultural activities, and should build on existing farmers' facilities, experience etc. with techniques that are modified to suit. A knowledge of a wide range of species and their characteristics, often for multiple purposes, will be important.
ENVIRONMENTAL / GEOGRAPHIC CONTEXT
Climate - information available about forest reproductive material can be broadly divided into that concerned with tropical and sub-tropical species, and that concerned with colder climate species. Many developing countries are in the tropics, and a lot of current work with forest reproductive material aims to provide information geared towards these countries. However, many principles and practices are applicable in both regions. You may notice a bias towards tropical climates in this publication!