Agricultural Science 2020 Jamb Examination

Farm power sources include natural forces such as wind and solar, biological power from humans and animals, and mechanical power from engines and tractors. A plough, however, is not a source of power but an implement that requires a power source like an animal or tractor to function. It serves as a tool, not an origin of energy.

Human power is the most adaptable because it can be applied to a wide range of farm operations, regardless of farm size or terrain. While animals, wind, and solar have specific uses, human labour can be redirected quickly, does not require specialised conditions, and can handle both simple and complex tasks across farming activities.

Farm surveying involves taking accurate measurements of land and representing them in maps or plans. This process ensures proper farm planning, layout of structures, and land management. Unlike soil estimation or construction levelling, surveying provides quantitative and spatial data that can be used to guide agricultural development.

Overhead irrigation facilities such as sprinklers and pivot systems are most efficient on large-scale farms. They distribute water uniformly across wide areas, reduce labour costs, and can be mechanised. Other methods like flooding waste water, porous pipes are limited in scale, and the shadoof system is traditional and impractical for extensive farming.

A gunter's chain is a traditional surveying instrument used for measuring distances on land. It is made of linked metal segments and was widely employed before modern surveying tools. Its purpose is specifically for land measurement, not soil, slope, or livestock control.

Grain legumes are crops that produce edible seeds rich in protein, such as beans, cowpea, and pea. Unlike cereals like maize, sorghum, and millet that are mainly carbohydrates, legumes improve soil fertility through nitrogen fixation and are essential in human and animal diets.

Cassava is vegetatively propagated using stem cuttings, as the plant rarely produces viable seeds for large-scale farming. Stem cuttings root easily and develop into new plants, ensuring uniformity in growth and early establishment compared to other propagation methods.

Crops like cocoa, maize, and rice often require nursery stages for proper establishment. In nurseries, seedlings are raised under controlled conditions to protect them from harsh environments before being transplanted to the main field. This practice ensures higher survival and uniform growth.

Ginning refers to the mechanical separation of cotton fibres from their seeds. This process is unique to cotton production, ensuring the fibre is clean and suitable for spinning into yarn. The term does not apply to crops like kenaf, cocoa, or groundnut.

Guinea grass, widely used as a pasture crop for feeding livestock, is scientifically known as *Panicum maximum*. It is a highly nutritious, fast-growing grass that adapts well to tropical conditions. Other names listed correspond to different grass species but not guinea grass.