FOREST FERTILIZATION IN GHANA: CONCEPTUAL BACKGROUND AND CASE STUDY WITH CEDRELA AND TEAK IN POLYPOTS

摘要

Ghana's Forestry Master Plan (1996-2020) proposes to establish 200,000 hectares of forest plantations on degraded lands in reserved forest. Since the lands are poor in nutrients, it was thought that fertilizer and/or other forms of nutritional enhancement will have to be made in the field or at the nursery as an effective way to increase nutrient uptake. The case study was designed to determine the effects of 15:15:15 (N:P_2O_5K_20) fertilizer solution on growth of Cedrela (Cedrela odorata) and Teak(Tectona grandis) in polypots in the nursery. Additionally, the study was to determine the optimum concentration of the fertilizer solution to apply. For seedlings of both tree species in polypots filled with sandy loam soil, 200mL of 0.8gL~(-1) , 1.6gL~(-1) and 2.4gL~(-1) fertilizer solution were applied once a week. On other days when no fertilizer solution was applied, the potted soils were irrigated with water. The control plants were given only water at all times. Generally, the application of thefertilizer solution significantly increased stem height and diameter growth and produced greater whole plant, stem, leaf and root dry matter over the control. The optimum concentration of the fertilizer solution was found to be 1.6gL~(-1).Keywords: Seedling growth; Cedrela odorata; Tectona grandis; fertilizer solution; optimum concentration