List four cereal crops grown in West Africa [2marks] (b) State three benefits of…

Explanation

(a)Cereal crops grown in West Africa 
– Rice 
– Maize-Sorghum/Guinea corn 
– Millet 
– Acha/hungry rice 
– Wheat 

(b)Benefits of forests to the economic development of a country 
– Source of income to rural people 
– For research/educational purposes 
– Source of revenue to the government 
– Purification of air 
– Beautification of the environment 
– Tourist attraction 
– Source of raw materials for industries such as gum and latex 
– Checks soil erosion 
– Source of food 
– Sources of fuel wood 
– Controls flood 
– Serves as wind breaks 
– Provides employment 
– Checks desertification 
– Source of medicinal herbs  
– Induces rainfall/modifies the micro climate 
– Protects water bodies/water shed  
– Produces timber used for construction 
– canoes, furniture etc 

(c) Description of the life cycle of the variegated grasshopper

Diagram of life cycle

Description  
– The female lays eggs inside the soil around April 
– These hatch into nymphs around October and during the 4th instar stage. they migrate into the farm and continue to feed on cassava leaves up to the adult stage. 
– The cycle has no pupal stage (incomplete metamorphosis/wingless nymphs)
 – The early stages of nymphs may feed on other shrubs such as Chromolaena spp. (Siam weed) as alternative host and continue until they come in contact with a cassava farm 

(d)Cultural methods of controlling crop pests 
– Crop rotation 
– Proper and timely weeding 
– Good spacing of crops 
– Drainage 
– Pruning of diseased parts of plant Planting pest free crops 
– Proper tillage operations 
– Timely planting 
– Timely harvesting Burning crop residues 
– Flooding 
– Mulching 
– Planting pest tolerant varieties of crop 

(e)Uses of oil palm
 – Production of palm oil
 – Production of palm kernel oil
– Production of palm kernel cake 
– Making of brooms Making of foot mats 
– Trunk for construction