DEFINITION AND CHARACTERISTICS OF WEEDS

 

 

Subject : Agricultural Science

 

 

Topic : DEFINITION AND CHARACTERISTICS OF WEEDS

 

 

Class : Basic & / JSS 1

 

 

Term : Third Term

 

 

Week : Week 1

 

 

Instructional Materials :

 

• Pictures of weeds
• samples of weeds

 

Reference Materials

• Scheme of Work
• Online Information
• Textbooks
• Workbooks
• 9 Year Basic Education Curriculum

Previous Knowledge :

The pupils have previous knowledge of weeds in their previous lessons

 

 

Behavioural Objectives :  At the end of the lesson, the pupils should be able to

• define weeds
• mention at least four types of weeds
• enumerate the characteristics of weeds
• list  economic importance of weeds
• differentiate between weeds and crops

 

 

Content :

 

DEFINITION AND CHARACTERISTICS OF WEEDS

CONTENT

1. Definition of Weeds
2. Some Common Weeds
3. Characteristics of Weeds

 

Definition of Weeds

Weeds are plants growing where they are not wanted or cultivated. A plant may be weed in one farm but crop in another farm. For instance, a cowpea plant growing in a cassava plot is a weed.

Some Common Weeds

Sida acuta

	S/N	Names of Common Weeds	Botanical Names
	1.	Guinea grass	Panicum maximum
	2.	Bahama grass	Cynodon dactylon
	3.	Carpet grass	Axonopus compressus
	4.	Elephant grass	Pennisetum purpureum
	5.	Spear grass	Imperata cylindrical
	6.	Giant star grass	Cynodon plactostachyum
	7.	Northern gamba	Andropogon gayanus
	8.	Stubborn grass	Eleusine indica
	9.	Southern gamba	Andropogon tectorum
	10.	Aspilia Africana	African marigold
	11.	Centro	Centrosema pubescens
	12.	Calopo	Calopogonium mucunoides
	13.	Kuzu or puero	Pueraria phaseoloides
	14.	Stylo	Stylosanthes gracilis
	15.	Sun hemp	Crotolaria juncea
	16.	Mucuna	Mucuna utilis
	17.	Goat weed	Ageratum conyzoides
	18.	Stubborn weed	Arctium minus
	19.	Sensitive plant	Mimosa pudica
	20.	Blue feather	Commelina nudiflora
	21.	Pig weed	Amaranthus spp
	22.	Bush green	Amaranthus spinosus
	23.	Water leaf	Talinum triangulare
	24.	Sedge plant	Cyperus rotundus
	25.	Tridax, PWD weed	Tridax procumbens

 

Characteristics of Weeds

Weeds have the following characteristics:

1. Weeds produce many seeds.
2. They can survive in adverse soil condition.
3. They grow very fast.
4. They have the ability to survive adverse soil and climatic conditions.
5. The seeds can remain dormant in the soil for a long time.
6. They are easily dispersed e.g by wind, animals, etc.
7. Seeds of weeds are highly viable.
8. They are resistant to trampling.
9. They produce large quantities of pollen grains/high reproductive capacity.
10. Most weeds are wind-pollinated.

 

 

 

 

Presentation

The topic is presented step by step

 

Step 1:

The class teacher revises the previous topics

 

Step 2.

He introduces the new topic

 

Step 3:

The class teacher allows the pupils to give their own examples and he corrects them when the needs arise

 

 

EVALUATION

1. Define weeds
2. Name 10 common weeds and their botanical names
3. State 5 characteristics of weeds

 

 

 

Conclusion :

 

The class teacher wraps up or conclude the lesson by giving out short note to summarize the topic that he or she has just taught.

The class teacher also goes round to make sure that the notes are well copied or well written by the pupils.

He or she does the necessary corrections when and where  the needs arise.

 

Assignment :

Prepare for the next lesson by reading about

 

CLASSIFICATION OF WEEDS