(a) State four ways in which weeds are beneficial to the farmer. [4 marks]
(b) Classify insect-pests in three groups based on their mode of feeding and give two examples of each [9 marks]
(c) State three ways by which pasture can be made available to cattle. [3 marks]
Explanation
(a) Ways in which weeds are beneficial to the farmer
- Weeds help in checking soil erosion
- Some weeds are useful as food for humans
- Some weeds serve as feed for livestock
- Certain weeds have medicinal properties
- Weeds can be ploughed into the soil to replenish soil nutrients
- Some weeds are used for roofmg, making mats, baskets etc
- Weeds can be cut and used as mulch
- For compost making
- Leguminous weeds harbour bacteria that help to fix atmospheric nitrogen into the soil
(b)Classification of insect-pests based on their mode of feeding and examples:
(i) Biting and chewing insects e.g locusts, grasshoppers, termites, mantids, the stick and leaf insects, beetles, leaf worms, army worms, budworms, crickets, larvae of lepidopetera
(ii) Piercing and sucking insects e.g capsids, cotton stainers, whiteflies, scale insects mealy bugs, green shield bugs, aphids, thrips, tsetsefly, ticks
(iii) Boring insects e.g beetles, weevils, stem borers, fruit borers
(c) Ways by which pasture can be made available to cattle
- Prepared as hay for livestock
- As silage
- Cut and carry as fresh fodder/zero grazing
- Animals can be taken out for grazing