Review of Practical Sessions – SS3 Horticulture and Crop Production Lesson Note (Third Term)

A practical review is a revision of the specimens, tools and skills that appear on the laboratory tables in the final Agricultural Science practical exam. The exam tests your observation (what you see), identification (what it is called) and application (what it is used for). This note covers tools, soils and rocks, crops and pests, and animal specimens.

Behavioural objectives

By the end of the lesson, students should be able to:

• name common hand tools, tillage implements and surveying equipment, and state how to maintain them;
• distinguish primary tillage from secondary tillage;
• identify sandy, clay and loamy soils, and igneous, sedimentary and metamorphic rocks;
• identify common crop parts, weeds and pests, and link each pest to the damage it causes;
• state the use of common feed types and animal processing tools;
• follow a simple routine to answer observation questions at a specimen station.

Why do practicals matter?

In Agricultural Science, the practical exam shows what you really know. You can read about a disc plough in a book, but until you see the curved steel and understand how it cuts through the earth, you do not fully know it.

The practical exam carries a large share of your final grade. This lesson is a walk-through of the most common things you will find on the laboratory tables during your final exam.

Which farm tools and machinery should you know?

Examiners like to display tools. You must be able to name them and, more importantly, state how to keep them from rusting or breaking.

Hand tools

Look out for the hand trowel, hand fork and secateurs.

• Maintenance: Always say “Clean after use” and “Oil or grease metal parts to prevent rust.”

Tillage implements

You will likely see models or photos of the disc plough and the harrow.

• The difference: The plough is for primary tillage (breaking the ground for the first time). The harrow is for secondary tillage (breaking the big clods of earth into fine soil).

Surveying equipment

These include the Gunter’s chain, ranging pole and theodolite. They are used for measuring farm boundaries.

Which soil and rock specimens should you know?

You will often see small jars of soil or rocks. You need to be a “soil detective”.

Soil types

• Sandy soil: Feels gritty, does not hold water, and falls apart when you squeeze it.
• Clay soil: Feels sticky when wet, holds too much water, and can be moulded into a shape.
• Loamy soil: The “Goldilocks” soil. It feels just right, has plenty of organic matter, and is best for most crops.

Rocks

• Igneous (e.g. granite): Formed from cooled lava. Very hard.
• Sedimentary (e.g. limestone): Formed from layers of sand or shells. You can often see the layers.
• Metamorphic (e.g. marble): Formed when heat and pressure change one rock into another.

How do you identify crops, weeds and pests?

This section is about knowing the plants and animals that help or harm your crops.

• Crop parts: You might be shown a corm (cocoyam), a bulb (onion) or a rhizome (ginger). You must know how they are planted.
• Weeds: Be ready to identify common weeds like tridax or spear grass. They are harmful because they compete with crops for sunlight, water and space.
• Pests: You might see a grasshopper, a weevil or a stem borer. Ask what the damage looks like. Does it chew the leaves? Does it suck the sap? Does it bore a hole into the fruit? Knowing the type of damage helps you pick the right pesticide.

Which animal science specimens should you know?

From the poultry house to the cattle ranch, these specimens show how we care for animals.

• Feed types: You might see bone meal, fish meal or concentrates. Bone meal is for calcium (strong bones and eggshells); fish meal is for protein (growth).
• Animal parts: An egg (check for a cracked shell), a feather or a bone.
• Processing tools: The Burdizzo (for castration), the ear notcher (for identification) or the dehorning iron.

How do you answer an observation question?

When you sit down at a specimen station, follow this routine:

1. Look closely. Note anything unusual (for example, “Specimen A is a leaf with yellow spots”).
2. Be specific. Write “Disc plough” instead of “Plough”, and “Sedimentary rock (sandstone)” instead of “Rock”.
3. Think of the farmer. If the examiner asks for the economic importance, think about how the specimen helps a farmer make money or why it causes a loss.

How should you revise for the practical exam?

Do not rely on cramming long definitions. Connect the tool to the job, the soil to the plant, and the pest to the damage. Spend time in the school farm or the laboratory looking at the real things. If you can identify these specimens and explain their uses, you will be well prepared.

Evaluation

1. State the difference between primary and secondary tillage, and name one implement for each.
2. Describe how you would recognise sandy soil, clay soil and loamy soil.
3. Name one example each of an igneous, a sedimentary and a metamorphic rock.
4. Name the farm part that is planted for onion, ginger and cocoyam.
5. State the use of the Burdizzo, the ear notcher and fish meal.

Assignment

1. Choose two farm tools from this note. For each, state what it is used for and how to maintain it.
2. List the three types of damage a pest can cause to a crop, and give one pest named in this note for each type where you can.