Page 265 - Primary Five Science

Advantages of weeds

 Some weeds are used as vegetables to man

 Some weeds are food to wild animals

 Weeds help to control soil erosion since they cover the soil

 Weeds rot and turn into manure. They increase the organic

matter content of the soil as they continually grow and die.

 Some of the weeds act as medicine

Disadvantages of weeds

 Harbour insect-pests & disease pathogens

 Weeds compete with crops for plant nutrients

 Some weeds are poisonous to man and livestock

 Weeds lower the crop yields

 Increase in the cost of cultivation

 Block the flow of water in irrigation channels