Judi’s Reviews > The New Encyclopaedia Britannica Set, Volumes 1-30 > Status Update

III. Harvesting and crop processing
HARVESTING MACHINERY
Harvesting machinery oil generally classified by crop: reapers for cutting cereal grains and threshers for separating the seed from the pant. The more modern combine cuts, threshes, and cleans the grain in one operation. Corn (maize) harvesting is performed by mechanical corn pickers that snap the ears fro the silk so that only the grain and cobs are ...

Mechanical problems. Mechanization faces many obstacles before wide adoption is possible in topical regions. Difficult soils, stones, stumps, abundant labour, resistance from farmers, lack of incentives, lack of skills, lack of capital, low wages, high cost of machines, lack of dealer service, fragmented land ownership, all contribute to slow development of mechanization. Tropical soils differ markedly from ...

Fallow system and tillage techniques, Dryland farming is made possible mainly by the fallow system of farming a practice dating from ancient times. Bascally, the term fallow refers to land that is plowed and tilled but left unseeded during a growing season. The practice of alternating wheat and fallow assumes that by clean cultivation the moisture received during tha fallow period is stored for use during the...

Biological controls. the question of using biologicall controls has always been of considerable public interest. The control agents include parasites, predators, diseases, protozoa,, and nematodes that attack the insect pests. Biological controls cannot replace insecticides entirely, because nature provides for the survival of both beneficial and destructive insects. Before the population of a parasite or predator..

Monoculture. The practice of growing the same crop each year on a given acreage, monoculture, has not been generally successful in the past, because nonlegume crops usually exhaust the nitrogen in the soil with a resulting reduction in yields; this is particularly true in humid regions. The advent of low-cost nitrogen fertilizers, however m had induced reconsideration of the possible advantages of monoculture.

Methods of application. Fertilizers may be added to soil in solid, liquid, or gaseous forms, the choice depending on many factors. Generally, the farmer tries to obtains satisfactory yield at minimum cost in money and labour.
Manure can be applied as a liquid or a solid. When accumulated as a liquid from livestock areas, it may be stored in tanks until needed and then pumped into distributing machine or into ...

The economics of fertilizers. The practical goal is to determine how much nutrient material to add. since the farmer wants to know how much profit to expect if he buys extra fertilizer, the tests are interpreted as an estimation of increased crop production that will result from nutrient additions. Cost of nutrients must be balanced against value of crop or even against alternative procedures, such as investing ...

Fertilizing and conditioning soil. Soil fertility is the quality of a soil that enables it to provide compounds in adequate amounts and proper balance to promote growth of plants when other factors (such as light, moisture, temperature, and soil structure) are favourable. Where fertility of a soil is not good, natural or manufactured materials may be added to supply the need plant nutrients; these are called ...

On modern mechanized farms, plow bottoms are connected to tractors either as trailing implements or internally. One or more bottoms may be so attached (Figure 2). They are found paired right and left occasionally (two-way), with the advantage of throwing the furrow slice in a constant direction as the turns are made. A variation is the middle breaker, or lister, which is bottom equipped with both right- and ...

I. General techniques
SOIL PREPATION

Mechanical processing of soil so that it is in the proper physical condition for planting is usually referred to as tilling; adding nutrients and trace elements is called fertilizing. Both processes are important in agricultural operations.
Tilling. Tillage is the manipulation of the soil into a desired condition by mechanical means; tool are employed to achieve some ...