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by Lars Schmidt

The Field Manual refers to the three conventional macropropagation methods, viz. propagation by cuttings, air-layering and grafting. Micropropagation/tissue culture, although a way of vegetative/clonal propagation with wide use in Tree Improvement Programmes, is considered to differ so much from the conventional macro propagation methods and in itself so comprehensive, that it will be dealt with in a separate Field Manual.

There are several ways of vegetative propagation. The three main types in forest tree propagation are grafting, air-layering and the use of cuttings. The three types are referred to as macropropagation, as alternative to micropropagation or tissue culture. Propagation by cuttings is the most convenient and cheapest method and usually preferred when possible. Air-layering is a variation of propagation by stem cuttings in which root formation is initiated before the plant part is separated from the mother tree. In grafting, the shoot (scion) of the desired tree is joined with a root (stock or root stock) of different genetic origin.

Which methods of propagation to be used in a particular situation is a matter of experience with the individual tree species plus the purpose and conditions of the propagation. The methodologies of vegetative propagation should be adapted to the individual plant species. The same method may work differently at a different time of the year, etc. The present guide is restricted to dealing with only the most basic methodologies and concepts, upon which the field worker may adapt his own variation according to his specific species and conditions.