The abundance of plant pests in the tropics, including weeds and disease, makes agriculture successful mainly in the plantation system, where needed control measures can be financed. The alternative is to move from deteriorated land to newer fields; this practice of shifting agriculture has also been common, because tropical soils lose their productive capacity so rapidly.
The size and number of tractors is dictated by the size, nature and profitability of the farming enterprise as well as by how many (if any) operations (e.g. plowing, planting, spraying, harvesting) will be serviced by local contractors. For example, the capital cost of purchasing a harvester to harvest a small area of a moderate value crop is often prohibitive.

Oil from oilseeds such as rapeseed, corn oil or sunflower oil, needs to be esterified to reduce its viscosity close to that of diesel before use in a diesel engine. The oil from oilseeds cannot be regarded as a potentially economic byproduct in the same way as sugarcane bagasse, a byproduct of sugar manufacture used as feed stock for manufacture of car alcohol fuel, or straw from cereals, used as fuel in boilers, are so regarded. 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.

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