by
Christel Palmberg
Forest Resources Division
Forestry Department
FAO, Rome, Italy
A prerequisite for any planting programme is an assured source of seed supply. Whether seed is collected locally or procured from elsewhere, its quality will determine not only the number of sound seedlings raised but also their subsequent survival and growth. “Quality” refers to: (i) the physiological quality of the seed, which depends on factors such as timing and methodology of collection and the handling and treatment of the seed; and (ii) the genetic quality, which depends on inherent characteristics of the stand from which seed is collected, the number of trees involved in pollination of the ovules (and, thus, the probability of inbred or “selfed” - i.e. self-pollinated -seed), and the number of mother trees used as sources. The genetic quality of the seed will also determine the value of the stand grown from it for subsequent seed collection and for selection and breeding work. It will thus have long-term effects on the development of additional local plantation programmes.
For many species the demand for forest tree seed on the world market exceeds supply, Moreover, the majority of seed of tropical/sub-tropical arboreal species moving in international trade today is poorly documented or not documented at all. This is partly because of a tendency to accept whatever seed is available, but mainly because of lack of realization of the fundamental importance of adequate documentation on seedlots used for plantation establishment, tree planting and experimental work.
In view of the above and other commonly encountered ambiguities in seed orders, FAO's Forestry Department strongly recommends that the following points be taken into consideration when procuring seed:
If a species has not been tried before, order only small quantities of seed for use in statistically sound experiments, and always include local species as “controls” in such trials. If the urgency for planting is great, use proven species. Experiences on species behaviour from other countries or planting regions can give some indications of which species are of potential value for specified conditions and uses and therefore should be included in experimental work, but can never serve as a substitute for locally established trials.
Pay attention to number of seeds per kilogram and do not over-order.
Always demand a certificate from the supplier which gives information on origin and provenance (latitude, longitude and altitude, as a minimum) and, ideally, the number of mother trees used as sources. If the seed is to be used for experimental purposes or for the development of local seed production or breeding populations, additional information is needed on stand characteristics and earlier treatments.
If an introduced species is to be used on a large scale and the best or most likely provenances for each planting zone have been experimentally determined, give top priority to the procurement of semi-bulk quantities of seed from a reliable supplier for the establishment of local seed stands, managed for maximum seed production and aimed at making the country or planting region self-sufficient in seed.
