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Saul Gwakuba Ndlovu
Land tilling farmers in Southern Africa have begun preparing their fields, and are reading the sky for signs and symptoms of the 2013-2014 rainy season.
Meanwhile, the rain-bearing inter-tropical convergence zone is obviously still hanging over some southern parts of South Africa’s Cape Province and is being watched by every weather station in that country, Namibia, Botswana, Lesotho as well as in all other Sadc states.
It is most interesting that we in Zimbabwe show a great deal of concern about rain in our respective areas of domicile whether or not we are practically involved in farming.  Not only are we concerned about whether or not rain will be plentiful in a particular season, but also how hot or cold it is likely to be.

The are two climate factors (precipitation and temperature) of much concern to every farmer, especially crop farmers.  That concern is not misplaced because without adequate precipitation the farmers’ fields are doomed with excessive heat and his or her crop will wilt.
However, there is another very important farming factor that should be highlighted now more than ever to help the national land programme succeed.  Thousands of young Zimbabweans have recently moved on land some of which had never been tilled.

They need to be properly educated on this factor,  which is the soil. Soils derive their characteristics from such things as rocks from which they are formed and the climate of their locality. Decaying animal and vegetable matter also contributes to the characteristics of soils.  An interaction of all these will produce soils of different types.

In Zimbabwe, the average crop farmer does not describe his soils by more than merely saying it is either loam, sandy-loam, dark or red (igusu, ihlabathi, isidaka loba isibomvu) (gusivi, nsetjana, tjidaka kene sabasi).
The texture of any particular type of soil determines its ability to retain and transmit water, its colour indicates an abundance of otherwise organic material some of which is used as crop nutrients. Dark soils contain more of such organic matter, and red soil has high iron content.

Each type of soil is suitable for a particular kind of crop or crops.  A soil suitable for legumes, for instance may not be suitable for maize or rapoko.  It is extremely important that technical extension personnel of the Ministry of Agriculture should hold regular workshops to educate our new farmers about this particular aspect of our agricultural science.

Zimbabwe farmers must understand that the successful tilling of the crops does not depend on only adequate rain but very much also on the type of the soil the farmer has and what kind of plants he plants on it.  That is important.

Farmers must also understand what causes soil acidity, or alkalinity, and how they can deal with that problem to make their fields or gardens productive. Extension personnel should design effective syllabuses on these topics.

Our agriculture technicians can take a leaf out of the experience and lessons of United States physiographers who have analysed and classified their vast country’s soils, a scientific move that has greatly advanced the US agricultural productivity.
Their soil classification ranges from what they call aridisols to entisols. Aridisols derived their name from the word “arid” because they occur in arid regions.  They have little organic content and are very insignificant of agriculture value.

There is an acidic type called spodosols whose nutrient content is low. It is found in moist, cool regions and is good only for those crops that thrive on alkaline soil.  The American also identifies what they named mollisols, a grassland type of soil found in sub-humid and semi-arid regions.  Mollisols are dark, thick and also tend to be brownish with a loose texture and a high nutrient content.   They are very good soils for cereal production.  Second to mollisols are alfisols found in areas moist to allow for the accumulation of clay particles.  They are, however, not so moist as to cause leaching or water logging. Alfisols are divided into three subgroups.

Entisols are recent soils, too young to show the effects of their surroundings, so say  the US scientists.  These soils are I am sure, found in some parts of Zimbabwe because of similar geological and climatic reasons.  We need to study their effects on our ecology.
It would advance the scientific knowledge of our nation if the relevant ministries and Zimbabwean universities mounted some research in a bid to meet the national land programme, especially the empowerment campaign.

Saul Gwakuba Ndlovu is a former professional school teacher, war veteran and retired journalist.  He can be contacted on mobile 0734328136 and email [email protected]