Crop pests include insects, fungi and weeds. It is not common to combine insecticides, fungicides and herbicides (weedkillers) but rather to apply them as individual or single formulations.The pesticide applicator sprayer is normally tractor-mounted and the tractor power-take-off shaft drives the spray pump. Such sprayer equipment (Figure 6) can also be used to apply liquid fertilizer especially where foliar applications are relevant (e.g. cereals).
Typically, harvesting represents the final stage of crop production at field level and essentially brings the farming season to a close. In many cases, harvesting is the most labor intensive farm operation and not infrequently associated with the drudgery of rural life. The development of machines that could successfully harvest most if not all agricultural crops has been greeted with enthusiasm. And yet challenges remain.
Primary power sources are many and varied including solar, wind, hydroenergy and geothermal, which may be used to power stationery equipment (wind, hydroenergy), to provide heating or cooling (solar, geothermal) or to generate electricity (wind, hydroenergy) to service a multiplicity of on-farm activities (see also, Energy Sources: Renewable and Non Renewable).Cereal straw and other dry byproducts (wood chips) may be used in small on-farm boilers typically to generate heat for drying harvested crops (cereals, oilseeds) or space heating (greenhouses, residential). Furthermore, biogas (predominantly methane) generated from animal wastes (e.g. pig slurry) by anaerobic digestion may also be used to power on-farm boilers typically to generate heat and also electricity in larger and more sophisticated installations.Even though bioethanol is an outstanding renewable engine fuel, it is more suited to Otto gasoline (petrol) than to farm diesel engines. Electricity may be generated from a range of renewable sources including wind, wave, hydro and biomass, but on-farm generation is unlikely except on a small-scale or on the basis of specialized energy or wind-power farms.
How the economics of such an approach evolve depends on the commitment of the international community to attain such sustainable and environmental goals. There has been a substantial global investment in agricultural mechanization and automation by governments, industry, farmers and international agencies. In general, the return on investment has been spectacular.