Observations on New Techniques for the Direct Sowing of Exotic Softwoods in East Africa

Abstract

The experiments described were carried out at the East African Agriculture and Forestry Research Organisation during 1963 with the object of developing reliable techniques for the establishment of exotic conifers by the direct planting of seed. The factors that militate against success have been shown to be: drought, the transposition or burying of seeds by soil erosion, and sun scorch of the tender seedlings. The date of sowing is also a factor probably affecting the degree of success obtained. The success of the sowings depends on the provision of 'aids' to augment the supply of available soil moisture and to ensure that there is adequate protection of the seeds and seedlings from physical hazards. A bamboo protective sleeve and a rainfall conductor stick have been shown to be effective in satisfying these requirements. The work includes investigations into the soil moisture balance in the first foot of soil, the root development of the young trees under the different treatment regimes and the effect of rainfall intensities on the collecting efficiency of the rainfall conductor sticks.