Weeds 

Back to: Agricultural Science Primary 4

 

Welcome to class! 

In today’s class, we will be talking about weeds. Enjoy the class!

Weeds

Meaning of weeds

A weed is any plant that grows where it was not planted at a particular time. It is an unwanted plant in that location.    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 a grass that is growing in a cassava farm. Such a plant must be removed in time.

Types of weeds

There are many types of weeds. Some are grasses, some stand erect, some creep on the ground, while some climb on or around other plants.

• Examples of Grasses are elephant grass, spear grass, giant star grass and guinea grass.
• Examples of erect weeds (These are weeds with short, erect stems). They are goat weed, Aspilia Africana and Mimosa plant.
• Examples of creeping weeds (These are weeds that creep on the ground). Common ones are Bahamas grass, carpet grass and pigweed.

Importance of weeds to farmers and the environment

1. They compete for space, water, and light with the planted crops on the farm.
2. They Compete with planted crops for plant foods (nutrients)
3. They reduce the yield of harvested crops.
4.  They Reduce the quality of harvested crops and Invites disease and pests to the planted crops
5. Control of weeds increases the cost of producing farm produce.
6. Overgrown weeds make our environment bushy and dirty
7. Bushy environments keep snakes, scorpions, and other dangerous animals always.
8.  Weeds help to check soil erosion.
9. When some weeds die and decay, they form organic matter and add nutrients to the soil.
10.  The seeds of some weeds mix with grains of crops and reduce the market value, e.g. rice paddy.

Evaluation

1. What are weeds?
2. Mention the three groups of weeds there are.
3. Give an example each of the groups mentioned.

Weekend assignment

1. State and explain four importance of weeds to farmers and the environment.

 

In our next class, we will be talking about Methods of Weed Control.  We hope you enjoyed the class.

Should you have any further question, feel free to ask in the comment section below and trust us to respond as soon as possible.

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