PRIMARY PRODUCTION
93
Six to eight crops are harvested annually from the intensively cultivated land which is kept permanently under vegetables. The main varieties are white cabbage, flowering cabbage, turnips, leaf mustard, Chinese kale, Chinese lettuce, tomatoes, water spinach, string beans, watercress and cucumbers. Cauliflower, cabbage, lettuce and tomatoes are produced in great quantity during the cool months and their quality is excellent. This intensive produc- tion of vegetables takes place on both fertile and comparatively infertile land and is made possible by heavy dressings of manure. Nightsoil is used on about three-quarters of the area and, in its place or as a supplement, pig and poultry manure, peanut cake, duck feathers, bone meal and compost are also applied. The use of artificial fertilizers is increasing, usually as an addition to the organic manures. Plant diseases are less important than insect pests and insecticides are very popular. Little or no attention was given to the selection of seed of local vegetables in the past, but the Agriculture and Forestry Department is devoting more and more attention to seed selection of local vegetables as well as variety trials with winter vegetables grown from imported seed.
Sweet Potatoes. This crop is grown for both the tubers and the vines which are used for pigfeed. It grows on dry land and about 1,850 acres were planted as a main crop, chiefly for tubers. Two crops are harvested per year with an average yield of 12 tons per acre. At an average market price of $18 per picul, this is an annual value of $6,714,000. A catch crop of sweet potatoes is also grown on 3,700 acres of paddy fallow, after the second paddy harvest. This crop is also used mainly for pigfeed vines.
Other Field Crops. About 1,468 acres are cultivated in many small plots for such field crops as peanuts, taro, radish, yams and sugarcane. These are grown mainly for local consumption.
Fruit. Fruit production is not yet substantial but it is expanding. The main varieties grown include wong pei (Clausena lansium), lemon, tangerine, Japanese apricot, guava, papaya, lychee, pine- apple and orange. There are no accurate statistics available, but roughly 42,272 piculs of assorted fruits were harvested during the year, valued $3,135,930.
Crops and Fruits for Export. A narrow range of fruits and crops is prepared for export to Chinese living overseas, mainly in the United States of America. Although the quantities exported