PRIMARY PRODUCTION
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The Colony continued to be free from rabies and rinderpest. The incidence of foot and mouth disease was not serious, though there were some 280 outbreaks of a mild type in both cattle and pigs. Some 22,000 cattle and pigs were inoculated against foot and mouth disease types 'O' and 'A', and 2,000 against type 'Asia I'. Slightly less than 50,000 pigs were inoculated against swine fever and some 7,000 cattle were inoculated against rinderpest, with locally produced vaccine. In all 16,634,000 doses of Ranikhet vaccine and 2,484,000 doses of intranasal-drop vaccine were used for the prevention of Newcastle disease in poultry. Farmers are making more use of the livestock advisory services of the Agriculture and Forestry Department.
FORESTRY
The Agriculture and Forestry Department is responsible for forestry generally, and for the direct afforestation of water catch- ment areas, protection of vegetation on Crown lands, assistance to village forestry, and amenity planting in catchment areas. A thick vegetative cover is essential to prevent silting of reservoirs and erosion, and to help streams to flow more regularly by inducing as much water as possible to remain in the soil. Well-managed forests are an ideal way to achieve this. Elsewhere forestry can provide timber and fuel for local consumption and help improve rural economy.
It is only in recent years that any serious attempt has been made to carry out afforestation on a large scale, and the landscape is now undergoing a noticeable change as plantations become established. Generally hills are predominantly grass covered, with a thicker cover of shrubs in some places and patches of scrub forest in remoter and less accessible areas. Thickly-wooded areas also occur where the vegetation has been protected against cutting and fire, as on Hong Kong Island and around villages. Villagers cut grass for fuel and this practice, combined with the prevalent hill fires of the dry season, has brought about the more or less complete destruction of vegetation, followed by soil erosion, in many parts of the Colony. Villagers often have forestry lots on the lower hill slopes, but the trees, mostly pine, are generally so scattered and badly lopped that they rarely alter the barren aspect of the land.