Weeds Care Control And Elimination
Agricultural Science
Primary 3
Second Term
WEEK 10&11
Topic: WEED
Subtitle: Meaning of weed
Learning Objectives: At the end of this lesson, pupils should be able to:
1. Define weed
2. State 3 measures of controlling weeds
3. State the characteristics of weed
INSTRUCTIONAL MATERIALS:
The teacher will teach the lesson with the aid of: charts and pictures showing the different types of house.
Resources and Materials:
Scheme of work
All relevant materials
9-Years Basic Education Curriculum
Online information
.Building Background/connection to prior knowledge: pupils are familiar with the topic in their previous classes.
Content
Description of a Weed
There are numerous definitions of a weed, including:
• a plant out of place and not intentionally sown
• a plant growing where it is not wanted
• a plant whose virtues have not yet been discovered. (R.W.Emerson)
• plants that are competitive, persistent, pernicious, and interfere negatively with human activity (Ross, et. al.)
Cultural weed control – One of the easiest ways to control weeds is through prevention or cultural control. Close planting in the garden can reduce weed growth by eliminating open space. Cover crops are good for this as well. Adding mulch will prevent light from getting to weed seeds and prevents growth. Mechanical weed control –
Mechanical control of common weed plants can be accomplished through hand pulling, hoeing, digging or mowing (which slows growth and reduces seed formation). While these methods are effective, they can be time consuming.
Chemical weed control
Characteristics of weeds
Certain characteristics are associated with and allow the survival of weeds. Weeds posses one or more of the following:
a) abundant seed production;
b) rapid population establishment;
c) seed dormancy;
d) long-term survival of buried seed;
e) adaptation for spread;
f) presence of vegetative reproductive structures; and
g) ability to occupy sites disturbed by human activities.
Weeds are troublesome in many ways. Primarily, they reduce crop yield by competing for water, light, soil nutrients, and space. Other problems associated with weeds in agriculture include:
a) reduced crop quality by contaminating the commodity;
b) interference with harvest;
c) serve as hosts for crop diseases or provide shelter for insects to overwinter;
d) limit the choice of crop rotation sequences and cultural practices; and
e) production of chemical substances which are toxic to crop plants (allelopathy), animals, or humans.
Strategies& Activities:
Step: Teacher revises the previous topic.
Step 2: Teacher introduces the new topic.
Step3: Teacher explains the new topic.
Step4: Teacher welcomes pupils questions.
Step5: Teacher evaluates the pupils.
Assessment & Evaluation:
1. Define weed
2. State 3 measures of controlling weeds
3. State the characteristics of weed
Wrap up(conclusion)
Teacher goes over the topic once again to enhance better understanding.
ASSIGNMENT
1. Define weed
2. State 3 measures of controlling weeds
3. State the characteristics of weed