New Zealand Journal of Forestry (1980) 25(2): 144–171
©New Zealand Institute of Forestry
Planting stock quality: a review of factors affecting performance.
C. G. R. Chavasse
Most research into treatments and quality of planting stock relies on measurements of the seedlings for one to three years after planting out. Numerous variables affect the seedlings throughout growing, handling and planting, and include the effects of both the nursery and the forest site, and of site preparation methods, which are superimposed on genetical variation. The mechanical, meteorological, biological and other factors affecting the performance of seedlings certainly have physiological effects, which must often be complex. While these may in time be elucidated using controlled-climate laboratories, the final evaluation must always be the performance of the seedlings in the forest.
This paper notes some of the factors involved, drawing mainly from N.Z. Forest Research Institute experience over the last ten years, supplemented by limited outside evidence. The scattered information on these factors is voluminous, but would have to be extracted from numerous papers and reports often covering other subjects. Even the New Zealand references have been limited, mainly to those covering nursery and establishment research on radiata pine (Pinus radiata). For example, no attempt has been made to study papers on genetical effects, however important they may be, and there are few references to studies of soils and nutrition, or to detailed physiological research.
It is concluded that the only reliable way of evaluating a seedling is to know, as precisely as possible, the history of the seedling from seed collection until the time of evaluation.