Page 51 - Agriculture_Form_3

Agriculture for Secondary Schools

2. For identified pests and diseases, suggest effective ways of managing them.
Then, practise the methods on the school farm.
3. Write a report and keep it in your portfolio for sharing.

FOR ONLINE READING ONLY
Exercise 3.3

1. You want to grow sorghum in a dry area. Choose the best water management
practice you will use to keep the crop healthy. Explain why you preferred the
practices.

2. You notice sorghum plants turning yellow and drying out. What could be the
cause, and how can you solve the problem?

3. A sorghum farmer applied manure to a selected part of the field and did not
apply to the rest of the field. What differences do you expect in plant growth,
and why?
4. A farmer reported that weeds are significantly reducing sorghum yields in a
field. Recommend at least three effective weed control methods the farmer
can use, and explain the reason behind each method.

5. You notice that your sorghum field is attacked by quelea birds. Suggest at
least three methods you can use to manage bird damage. Explain why you
chose those methods over the others.

Harvesting, postharvest management and marketing of sorghum

Sorghum matures in 3 to 6 months after sowing. The exact time varies depending
on the variety and growing conditions. When sorghum is ready for harvest, the
grains become hard and dry. The leaves turn yellow, dry out, and the stalks lose
moisture. When pressed between fingers, the grains become too hard to be pressed
with fingernails. Farmers with small to medium-sized fields harvest sorghum by
hand, using knives or sickles. Some cut only the heads of the sorghum plants
and leave the stalks behind. Others harvest the whole plant and later separate
the grains from the stalks. In larger fields, combine harvesters are used. These
machines cut, thresh and clean the grains in one process. This method is quick,
although expensive. In Tanzania, hand harvesting is the most common method. It
is cheap but slow. Small machines can be used for cutting and threshing, which
are faster, though they can be relatively expensive to maintain.

42 Student’s Book Form Three

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