Somewhat better results have been achieved in the expansion of irrigation. In the 1965-70 period the irrigable area increased at an annual average of 44,000 acres from 2.25 million to 2.47 million acres, or 21 percent of the cultivated land. Under the Sixth Five-Year Plan (1971-75) 494,000 acres are to be added to the irrigable area, raising the total irrigable acreage to 26 percent of the cultivated land. During the first two years of the plan period 124,000 acres were equipped for irrigation, and 80,000 acres were to be made irrigable in 1973. In order to complete the five-year irrigation program on schedule, therefore, it would be necessary to bring under irrigation 270,000 acres in the last two years of the plan period—a task not likely to be accomplished in the light of past experience and of available resources.
Only about 70 percent of the irrigable acreage was actually irrigated in the 1965-70 period. Although the irrigated area of 1.7 million acres in 1970 represented an increase of 21 percent of the acreage irrigated in 1965, it was 17 percent smaller than the acreage irrigated in 1968.
Primitive gravity irrigation is practiced on about nine-tenths of the irrigated area. Water is distributed over the fields from unlined earthen canals by means of furrows dug with a hoe. The work entails hard manual labor, and a single worker can handle only about 1.25 to 2.5 acres per day. The timing of the water application and the quantity of water used are not properly adjusted to the needs of the various crops, so that the increase in yields is only half as great as that obtained under optimum conditions, and about half the water is wasted. The network of irrigation ditches also impedes mechanical cultivation of the fields. Improper irrigation and drainage techniques have raised the groundwater level excessively in several districts and have caused various degrees of soil salinization in areas totaling more than 39,000 acres.
The five-year plan program for new irrigated areas calls for the construction of stationary sprinkler systems over 25,000 acres; 469,000 acres are to be provided with portable sprinkler systems. Reconstruction and modernization of existing basic facilities are to be limited to the lining of canals. The ultimate longer term goal is to establish fully automated stationary sprinkler systems in most irrigated districts. The main problems in carrying out the irrigation program, in the view of an irrigation authority official, are posed by the paucity of investment funds allotted for this purpose and the contradictory nature of some of the program's aims. Additional difficulties are presented by the shortage of irrigation pipes and materials for their fabrication, inadequate experience in the manufacture of advanced irrigation equipment, and the lack of facilities for experimentation and testing.
Cropping Pattern
The area of field crops amounted to almost 9 million acres in 1970; it had declined by 887,000 acres after 1960. The proportions of this acreage devoted to the major types of crops were: grains, 62.5 percent; industrial crops, 14.6 percent; feed crops, 18.7 percent; and vegetables, potatoes, and melons, 4.2 percent. In accord with the government's policy of intensifying agricultural production, the acreage of bread grains had steadily declined, so that in 1970 it constituted somewhat less than half the total grain acreage. The area of feed grains remained fairly stable; a decline in corn acreage was virtually balanced by an increase in the acreage of barley. A slight reduction also took place in the acreage of pulses, but the area under rice expanded by 70 percent.
Whereas the total area of industrial crops changed very little in the 1960-70 period, a significant shift took place in the relative size of the individual crop areas. While the acreages of oilseeds and tobacco expanded significantly, the acreages of fibers, particularly cotton, and of essential oils and medicinal plants declined sharply.
The area devoted to vegetables expanded by 20 percent. The tomato acreage expanded at about twice that rate and accounted for one-fourth of the vegetable acreage in 1970; tomatoes constitute an important export crop. The potato acreage, on the other hand, declined by roughly 20 percent during the period.
The area of fodder crops suffered a substantial decline, particularly in the case of annual grasses and silage crops. The loss was only partially offset by the expansion of the perennial grass acreage.
Rapid expansion also took place in the areas of apple orchards and vineyards. The acreage of bearing apple trees increased by about 70 percent in the 1970-70 period. During the same period the acreage of producing vineyards grew by 24 percent, while the acreage of table grapes increased by 2.3 times. Fruits and grapes are also important export commodities. Expansion of the total acreage under fruit trees and berries, however, was much slower—17 percent in the 1960-68 period—and a decline in the acreage set in after 1968. In the spring of 1973 Todor Zhivkov, the communist party leader, called for decisive action to halt the unfavorable trend. He reported that plans for orchard and berry plantings were not fulfilled in 1972; that from 27,000 to 40,000 acres of orchards had been uprooted over a period of a few years; and that the vineyard acreage had declined by 25,000 acres compared with the acreage in 1968. Reasons for these developments had not been made public.