Cupressus lucitanica miller, growth and yield studies in Kenya

This is a growth and yield study of Cupressus lusitanica Miller under the present sawtimber management schedules in Kenya. It is based on 133 permanent sample plots maintained by the Kenya Forest Department. Site, size quality and site indexing systems are discussed and site index curves for C. lusitanica in Kenya constructed, using the periodic dominant height increment method and a reference age of 20 years. The mean diameter of thinning, basal area and basal area development are discussed and the relevant equations derived. Basal area increment for understocked, normal and overstocked stands are also studied. Understocking was found to result in lower basal area increment at early age (up to age 20 years on average site). This indicates that the three first thinnings are probably too heavy. Finally a volume yield table is constructed for the average site index class in Kenya (S.1. 24.1). The volume is calculated using the tree volume equation by H. L. Wright (1999) which has dominant height and diameter at breast height as independent variables. The current and mean annual volume increments are discussed and the biological rotation for the average site in Kenya determined.