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which a system of small dams would be used to retain the water. These dams would provide a valuable addition to the water resources of the Units, which in the absence of surface (and roof) collection of various types are likely to be meagre in the Kongwa Region,

The soil and water conservation system thus developed will certainly form part of a general land and water utilisation policy aimed at the optimum develop- ment of the whole region under the Corporation's control. In particular, this policy will be necessary for the provision of water and grazing for the cattle herds required to feed the staff of the Units, and for irrigation water, in particu larly suitable areas, for vegetable production.

Evidently, however, many of these developments must await the completion of clearing before any significant quantity of heavy machinery is available for their execution; and they must turn, too, on the full practical demonstration that the technical success of the agricultural aspects of the scheme is certain.

A word needs to be said about wind erosion. Those who have had bitter experience of the dust raised from camps and roads in the turbulence zone of Kiboriani mountain, in which Kongwa itself lies, have talked of the development of dust-bowls. In fact, no wind erosion has been observed on the production Units except where ill-made and unsurfaced tracks have been pounded into dust by fast and heavy traffic. The natural tendency of the majority of the Kongwa soils to compact on drying is a valuable safeguard against move- ment of the soil by wind in the dry season.

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In the Western and probably in the Southern Province, the erosion situation is different from that at Kongwa. Firstly, the total precipitation is higher, and storms seem to be of rather longer duration. The extremely even topography-particularly at Urambo-opposes quick run-off of surplus rain- water, and where natural depressions or tree-stump cavities occurred, pools were frequently left for long periods, particularly in the grey soil. It seems certain that variable

that variable grade terraces, discharging into grassed-up water- courses, will have to be the standard pattern of conservation policy, but there will be the difficulty that the topography does not provide many obvious gullies. Ploughing will have to be carried out to leave marked open furrows, to aid drainage, and ridge cultivation will be of great value.

The broad, open, infilled drainage channels which occur in the Urambo Region and in Block B, Southern Province, will present considerable possibilities for rice and even fish-farming, provided they are developed in such a way as to take advantage of surplus water discharged from the terrace outfalls

Plant population

6. GROUNDNUT PRODUCTION

American experience (Stansel, 1935; Lovvorn and Kime, 1939; Parham, 1942 ; Department of Botany, Georgia Experimental Station, 1945) indicates that one of the most important factors in securing maximum groundnut yields is the establishment of a high plant population. It was evident before planting began, that the bad seed-bed conditions on the units and the general inexperience of the staff engaged on the planting work would make the establishment of satisfactory stands of plants difficult at Kongwa,

at Kongwa, particularly when the spasmodic character of the rainfall and the high temperature and evapora- tion rates of the sowing season were taken into account. Accordingly, a survey was undertaken by the Department, with the assistance of Unit staff, to determine the actual plant population on the production fields.

This survey was carried out during January, 1948.

Planting was in 28 in. rows, using at first a spacing in the row of 5 in. (theoretical populationg about 41,000). After a few days it became anpagent that the factors mentioned above, together with the poor quality of the seed

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