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Table 4
Estimated crop yields under traditional farming conditions in the Butembo test area
Crop
Reference
yield
(kg/ha)
Consumable yield (kg/ha)
S I (77) * S 2 (60) S3 (39) Valley soils
Banana 12,000 8,316 6,480 4,212 —
Cocoyam 10,000 6,930 5,400 3,510 —
Cassava 14,000 9,702 7,560 4,914 —
Sweet potatoes 10,000 6,930 5,400 3,510 —
Beans 1,000 663 500 311 1,200
Maize 1,200 792 618 392 1,440
* M ean agro-pedological index calculated considering the index values of the individual
m apping units and their surface area.
Table 5
N um ber of food portions of 2,220 Kcal produced per km 2 under traditional farming
in the Butembo test area
Suitability
class
Cultivable
surface area *
(ha)
Farm
size
(ha)
Number
of farms
Daily energetic
value of the
farm
(Kcalories)
Daily energetic
value of the
suitability class
(Kcalories)
Number of
food portions
of 2,220 Kcal
SI 30.91 2.2 14.0 13,322 186,508 84.0
S2 23.12 2.6 8.9 10,428 92,809 41.8
S3 4.63 3.0 1.5 6,730 10,095 4.5
Total/m ean 58.66 2.4 24.4 11,861 289,412 130.3
* The valley soils are excluded.
Expected consumable yield results for the different crops are given in table 4.
The conclusions for traditional farming in the Butembo test area, expressed
in number of food portions of 2,220 Kcalories, are given in table 5.
Intensive farming
Intensive farming requires adequate soil conservation practices, correction
of the cation balance up to a base saturation of 50 % with a Ca/ Mg/ K ratio
of about 75/18/7. The problem of phosphor fixation in tropical soils is
eliminated by the application of the required P. Further, the use of a maintenance
fertilizer application of N-P-K is required. Under these conditions
fallow land is no more required. Introduction of fodder crops in the crop
rotation and a few acres of forest land for fuel wood production is necessary.
Cultivation of an industrial crop (tea) should be foreseen, in order to provide
the necessary cash money.
The structure of the farm could be as follows :