Alternatively, it may be applied on the surface of the ground or crop (e.g. grass) using a tractor mounted centrifugal spinner or oscillating spout type applicator where the fertilizer is broadcast rather than placed in rows. Aerial application of fertilizers may also be used in locations inaccessible to tractors, as described in Fertilizer Applicators and Plant Protection Equipment (EOLSS on-line, 2002). Both pressurized (typically using ammonia) and nonpressurized liquid fertilizer applicators are also described. Protection of plants from diseases and pests is normally achieved by atomizing a liquid formulation containing the active pesticide ingredient through a small nozzle under pressure and spraying onto, beside or beneath the crop canopy, or by using granular pesticide applicators.
These characteristics of rental markets are confirmed by some data for tractor rentals in South Asia and machinery rentals in the Philippines. The Philippine data show that most farmers own their animals, carts, plows, and harrows. Harvesting and threshing equipment, tractors, and motor vehicles, however, are used on about five to seven times more farms than own them, which indicates that rental markets are extremely well developed. Generalization 7. Where rental markets are fairly easy to establish, farm size has much less influence on the size of machines. Subsidies. Subsidies may speed up mechanization.