The chief method employed for their destruction is spraying the swarms with arsenic. The districts with the greatest area under cultivation are Heidelberg, Witwatersrand, Pretoria, Standerton and Krugersdorp. The chief crops grown for grain are wheat, maize (mealie) and kaffir corn, but the harvest is inadequate to meet local demands.
These animals are of great use and profit to their masters, for their wool is very good and fine, particularly that of the species called pacas, which have very long fleeces; and the expense of their food is trifling, as a handful of maize suffices them, and they can go four or five days without water.
Though much land previously devoted to grain culture has been planted with vines, the area under wheat, barley, beans and maize is still considerable.
The staple diet of the labouring classes and small farmers is fish, especially the dried codfish called bacalhdo, rice, beans, maize bread and meal, olive oil, fruit and vegetables.
Oranges, lemons, grapes, passion fruit, figs, pine-apples, guavas and other fruits grow abundantly; while potatoes, onions, maize and arrowroot can be cultivated.
The staple diet of the Paraguayans is still, as when the Spaniards first came, maize and mandioca (the chief ingredient in the excellent chipa or, Paraguayan bread), varied, it may be, with the seeds of the Victoria regia, whose magnificent blossoms are the great feature of several of the lakes and rivers.
It is only in Kakhetia, where numerous mountain streams supply the fields and gardens of the plateau of Alazan, that wheat, millet and maize are grown, and orchards, vineyards and mulberry plantations are possible.
Wheat and maize are exported to the Aegean islands and to Turkish ports on the mainland; barley, oats and linseed to Great Britain; canary seed chiefly to Australia; beans to France and Spain.
Spices (cloves, cinnamon, nutmegs) were the chief articles of trade in the 18th century, and these with cotton, coffee, tobacco, sugar, maize and rice were the main crops grown until about 1850.
The fields of Tuscany for the most part bear wheat one year and maize the next, in perpetual interchanges, relieved to some extent by green crops.