Page 127 - Agriculture_Form_Three

Agriculture for Secondary Schools

After each layer is placed in the silo, the material should be compacted by trampling
or using heavy loads such as barrel filled with water or sand. In large-scale farming,
compaction is done by running a tractor over the material. Compaction has to be
done in order to exclude air in the silo. If air is allowed to remain in the silo, aerobic
microorganisms, e.g., clostridia bacteria cause silage materials to decay. It also

becomes bitter and smells bad. Such materials are not good for feeding livestock.
Therefore, the purpose should be to create anaerobic conditions in the silo. If
compaction is by human trampling, be cautious of trapping pockets of air inside
the stack. The edges of the storage must be well packed too. Figure 5.13 shows
materials in a pit silo and a sand filled drum for compaction.

Polythene sheet

Barrel filled with sand Chopped forage

Figure 5.13: Materials in a pit silo ready for compaction in silage making

The entire silage storage should be filled in one day and at a maximum two days.
If some of the previous day’s forage is not covered sufficiently, it will suffer from
aerobic deterioration causing the stack to heat up, with subsequent losses in both
quantity and quality. In case ensiling goes beyond a day, the stack should be covered
with a sheet of plastic or a thick layer of banana or palm leaves each night until it

is filled. This will minimise the amount of warm air leaving the stack which sets up
convection currents thus encouraging more air to enter. When the silo is full, cover
the material in the silo with a plastic sheet and finally fill the top with soil to make
it convex.

Student’s Book Form Three
116

10/01/2025 12:31
AGRICULTURE FORM 3 9.11.2022.indd 116
AGRICULTURE FORM 3 9.11.2022.indd 116 10/01/2025 12:31