Meaning and Common Weeds | Uses of Weeds | Methods of Controlling Weeds | Effects of Weed Control | Classification of Insect Pests | Damage done by Crop Plant Pests | Effects of Pests on Crop Yield JSS 1 Agriculture

AGRICULTURE

JUNIOR SECONDARY SCHOOL (JSS 1)

THEME – CONCEPTS AND MEDIUM OF AGRICULTURAL PRODUCTION 

TOPIC 5 –  METHODS OF WEEDS AND PESTS CONTROL

LEARNING AREA

• Meaning and Common Weeds

• Uses of Weeds

• Methods of Controlling Weeds

• Effects of Weed Control

• Classification of Insect Pests

• Damage done by Crop Plant Pests

• Effects of Pests on Crop Yield l

INSTRUCTIONAL MATERIALS

1. Charts and pictures of Weeds

2. Weeds specimen

3. Weed album

4. Herbicides

5. Charts and pictures of the pests of the Locality, and

6. Specimens of insect pest, formalin, kerosene, (for preservation), insect box, etc.

LEARNING OBJECTIVES

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

1. list the characteristics of weeds.

2. indicate the uses of weeds.

3. briefly discuss methods of weed control.

4. state the effects of weed control methods on vegetation and soil.

5. classify insect pests according to mouth parts.

6. describe the nature of damage done by crop plant pests.

7. state effects of pests on the crop yield.

CONTENTS OF THE LESSON

LESSON 1 – INTRODUCTION (MEANING OF WEEDS) 

Weeds are unwanted plants growing in the farm and other places. Any plant not planted on the farmland by the farmer and grow where they are not wanted is called a weed.

Weeds compete with the grown plant for food, water, air and space, such that the wanted plant may eventually die.

A good example of weeds is grass that is growing in a yam farm. Such a plant must be removed in time.

LESSON 2 – COMMON WEEDS

1. Elephant grass

2. Guinea grass

3. Spear grass

4. Giant star grass

5. bahama grass

6. Carpet grass

7. Pig weed.

LESSON 3 – CHARACTERISTICS OF WEEDS 

1. Easily Dispersed 

Plants cannot move but have many ways of getting around and grow easily. With the activities of man and animals make it easily spread or dispersed.

Seeds can be dispersed by wind, water, animals, and humans.

 

2. Long Dormancy 

Plants do not grow easily even under favorable environmental conditions for germination including, temperature, water, light, etc.

LESSON 4 – USES OF WEEDS TO THE FARMERS 

1. Weeds protect the soil from wind and water erosion.

2. Weeds retain the soil nutrients from plants use.

3. Weed keep and protect the microorganisms that increases soil nutrients for plants use.

4. Weeds are used cover yam from burning after planting.

5. Weeds are used for crops preservation and packaging.

6. Weeds are used for mat production.

7. Weeds are used for feeding livestock.

8. Weeds are used for herbal medicine.

9. Some of them are actually crops. For example, maize is a weed, if grown on yam farmland. The farmer may decide to keep it it is healthy and useful for yam.

LESSON 5 – ECONOMIC IMPORTANCE OF WEED

1. It reduces the crops production.

2. It reduces the quality of harvest.

3. It increases the cost of crops production.

4. It may poise the animals.

5. The cost of controlling weed is high.

6. It causes quicker wear and tear of farm implements.

LESSON 6 – EFFECTS OF WEED CONTROL METHODS ON VEGETATION AND SOIL 

1. Pollution of soil and ground water.

2. Contamination of livestock pasture.

3. Expose the soil to erosion – wind and water.

4. Destroy soil micro organisms.

5. It reduces the aquatic animals.

LESSON 7 – CONTROL METHODS ON VEGETATION AND SOIL

1. Biological Control 

This process involves using animals to feed on the weeds on a farm of tree crops that are fully grown, such as a citrus orchard, rubber plantation and palm plantation.

One disadvantage of this method is that the animals may also eat and destroy the wanted plants in the process.

 

2. Cultural Control 

Cultural control is the removal of weed by hands, cutlass or hoe.

It involves uprooting weeds with hands, cutlass or hoe.

This is also called manual control.

3. Chemical

A chemical is a man-made liquid or powder used for controlling or killing weeds.

It is also used for controlling or killing pets and diseases. This control is called weedicides.

LESSON 8 – MEANING OF CROP PESTS

Pests are organism that are harmful or damage farm crops. Common crop pests are as follows:

1. Beetle

2. Weevil

3. Grasshopper

4. Locust

5. Caterpillar

6. Termite

7. Rodents

8. Quela birds

9. Bats

10. Monkeys

LESSON 9 – CONTROL METHODS ON VEGETATION AND SOIL

1. Biological Control 

This process involves using animals to feed on the pests on the farm.

One disadvantage of this method is that the animals may also eat and destroy the wanted plants in the process.

 

2. Cultural Control 

Cultural control is the removal (or killing) of pests (insects) by hands, cutlass or trap.

This is also called manual control.

3. Chemical Control 

A chemical is a man-made liquid or powder used for controlling or killing pests and diseases spread by pests.

LESSON 10 – CLASSIFICATION OF INSECT PESTS BASED ON MOUTH PARTS 

1. Piercing and Sucking Insects 

1. Cotton stainers

2. Green shield bugs

3. White flies

4. Mealy bugs

5. Mirids/capsids

6. Fruit-piercing moths

7. Coreid bugs

8. Scale insects

9. Aphids

10. Cocoa thrips

2. Biting and Chewing Insects 

1. Locusts

2. Grasshoppers

3. Termites

4. Leaf worms

5. Armyworms

6. Crickets

8. Budworm

9. Caterpillar

10. Stick insects

11. Mantis

12. Rhinoceros beetles

3. Boring Insects 

1. Yam beetles

2. Beam beetles

3. Rice weevils

4. Maize weevils

5. Sorghum weevils

6. Stem borers

7. Larvae of Lepidoptera e.g. butterfly, moth

8. Pod borers

LESSON 11 – DESCRIPTION OF THE DAMAGE DONE BY THE CROP PESTS 

There are two (2) kinds of damage done by the crop pests – direct and indirect damage.

DIRECT DAMAGE 

Direct damage is feeding on crops leaves, burrows in the stems, fruits and leaves.

INDIRECT DAMAGE 

Indirect damage is the pests (insect pests) infect and transmit diseases like bacterial, viral, or fungal infection into a crop.

LESSON 12 – EFFECTS OF CROP PESTS ON YIELD

1. Pests infected seeds, crops, and vegetables.

2. Pests reduce market value of farm crops.

3. Pests reduce the quality of crops.

4. Pests eat up leaves, burrows in stems, fruit, or roots of crops

5. Pests reduce crop productivity.

LESSON PRESENTATION

TEACHER’S ACTIVITIES

The teacher,

1. demonstrates chemical control of weeds.

2. highlights the effects of weeds control methods on vegetation and soil.

3. displays pictures and charts of crop pests of the locality.

4. displays specimen of insect pests.

5. summarizes the lessons on the board.

 

 

STUDENT’S ACTIVITIES

The students,

1. practice weed control on the school farm.

2. study pictures and charts to familiarize self with the local crop plant pest.

3. bring insect pests and make insect box.

4. copy the board summary.

 

LESSON EVALUATION

Teacher asks students to,

1. mention two characteristics of weeds.

2. state two uses of weeds.

3. state two weed control methods.

4. explain two effects of weed control on the environment.

5. mention two classes of crop pests.

6. list two piercing and sucking insect and three biting and chewing insects.

7. describe the nature of damage done by crop plant pests.