Manual for establishing and managing Melia volkensii seed orchards in Kenya

Abstract

Melia volkensii is an indigenous drought tolerant and multipurpose tree species endemic to the Arid and semi-arid areas of eastern Africa. Its common names are Melia, tree of knowledge (English); Mukau (Kamba, Tharaka and Mbeere), Tile (Boran) Boba, Mbamba (Somalia, Oromo) Maramarui (Samburu), and Kirumbutu (Taita). Melia is a deciduous tree that attains a height of 6 to 20 m and an average diameter of about 25 cm. The crown is open while the bark is grey and fairly smooth. Leaves are bright green, up to 35 cm long, compound, with 3-7 deeply lobed leaflets that are densely hairy when young. The flowers are small, white and fragrant, arranged in loose inflorescences. Mature fruits are yellow later developing brownish patches due to the deposit of cork. The fruit is an ovoid drupe 3 to 4 cm long with each fruit containing one to five seeds that are enclosed in a very hard and thick endocarp (nut). The seeds are oval, about 2 cm long and 0.5 cm wide. There are about 200 seeds per kg of nuts, with the average number of seeds per kg of extracted seed ranging from 3000 to 3,500. At the radicle end of the seed is an appendage called the caruncle. M. volkensii occurs naturally in the semi-arid zone of Ethiopia, Somalia, Kenya and Tanzania.This Manual provides a guide on how to establish and manage Melia clonal seed orchards through documenting the process and experiences of establishing the first generation Melia seed orchards. It aims at assisting public and private tree seed producers, forestry and orchard managers in effective establishment and management of future seed orchards. The contents of this manual include introduction to the basic principles of seed production, documentation of the selection process of candidate plus trees and criteria used, scion collection from CPTs, grafting, and field establishment of clonal seed orchards. The manual also covers aspects of management of seed orchards including monitoring, weeding, pruning, reducing pests and diseases, and seed production.