Page 102 - Agriculture_Form_3

Agriculture for Secondary Schools

3. Your class treated pea seeds with Rhizobium before planting. Later, someone
suggests adding more nitrogen fertiliser.
(a) What could be a reason for suggesting addition of nitrogen fertiliser?

(b) What should be considered before applying the fertiliser?
FOR ONLINE READING ONLY

Management of weeds in common pea fields

Weed management is important for the healthy growth of the crop. Weeds
compete with peas for water, nutrients, sunlight, and space. If not controlled, they
can reduce plant growth, affect pod development, and lower yields. Some weeds
also attract pests and diseases. Weed control should begin early and continue
until the peas form a full cover on the ground. Delaying weed control allows
weeds to spread and makes them harder to control.
Weeds cannot be controlled well by just one method. A combination of methods
gives better results. Weed control should begin early when land preparation is
done to reduce weeds as much as possible. If weeds reappear before sowing,
recommended herbicide may be sprayed to control them completely. This helps
to ensure that the field is clean before sowing. After seedling emerge, mulching
with dry grass or crop remains can be done to cover the soil, suppress new weeds
growth and help retain moisture. If weeds appear later, they can be controlled by
hand-pulling or hoe weeding between the rows and around the plants.

Activity 6.7
1. Visit the school or home pea field and identify the different types of weeds
growing there.

2. Write down the names of weeds (identify by their local and common names),
explain how each weed affects pea growth and how it can effectively be
managed.

3. Divide the common pea field into seven small plots. Then,
(a) Apply a different weed control method in each plot as follows:

(i) In plot one, use a hand hoe.

(ii) In plot two, pull weeds by hand.

(iii) In plot three, plant cover crops between rows.
(iv) In plot four, apply mulch.

Student’s Book Form Three 93

17/09/2025 14:12
AGRICULTURE F3.indd 93 17/09/2025 14:12
AGRICULTURE F3.indd 93