5. The south of the Buenos Aires province and the central Pampa are the wheat zone. The bed of tosca, which is not far below the soil, does no harm to the wheat except in years of drought. The valleys, where the tosca is interrupted, and the dunes, where the soil is deep, are very carefully used for lucerne fields of limited extent. Wheat-growing seems now, both in this and the preceding zone, to have reached its limit, as the dryness makes it improbable that there will be any extension westward.
6. Lastly, the east of the Buenos Aires province, the centre of which is fairly indicated by the little town of Dolores, is the only part of the Pampean plain which has not been reached by agricultural colonization. The land lies low, and is badly drained. The only change that has taken place in the vegetation is a progressive improvement due to the hoofs of the cattle during their long stays there. This pastoral area is clearly limited in the south by the Sierra de Tandil. In the north it is continued in the more varied region that lies between Buenos Aires and the lower Salado, where the alternation of winter pasture on the dry lands and summer pasture in the valleys, encourages the best methods of breeding, and has made it the region of the dairy industry.
In the Entre Rios province the limit of the large estates of wheat and flax is marked by 32° S. lat. The part of Entre Rios which extends north of 32° and the Corrientes province do not strictly belong to the Pampean region.
Extensive breeding was the first form taken by white colonization on the Pampa. The word breeding is, in fact, hardly the correct name for an industry that mainly consisted of hunting, and was wholly distinct from the patient and advanced methods used at the same time in the northern provinces.
"The real wealth of the province of Buenos Aires," says Dean Funes, "was, and always will be, the trade in hides" (la pellejería).[87] A good part of the hides exported came from the hunting of the wild cattle and horses which had grown numerous on the area of the Pampa beyond the Rio Salado.[88] It was mainly after 1778, when trade with Spain had been authorized and there was an increased demand for hides, that the hunting of these ownerless beasts was taken up. Two thousand Spaniards from Buenos Aires, Santa Fé and Mendoza hunted every day, says D'Azara, killing an animal for each of their meals in addition to those they killed for hides. From 1775 to the Revolution, the Spanish Government made continuous efforts to regulate and reduce the massacre of the herds. It laid down penalties for every person selling hides that did not bear his own mark; it farmed out the right to hunt animals with no mark, and organized the destruction of wild dogs, etc. The ranches developed under shelter of this legislation. Still, the Revolution did not witness the end of this cattle-hunting. D'Orbigny took part in 1828 in two hunts of wild horses (baguales) in Entre Rios. The Argentine gaucho long retained the ways of a hunter rather than those of a breeder in the strict sense; witness Urquiza's soldiers who, says Demersay, during the campaign of 1846, when they could not find trees to which they could fasten their horses, killed cattle and tied the reins to their horns.
Passing from the hunting country to the zone of ranches, one notices that the main work of the breeder is to prevent his cattle from running wild. "The ranches of this country," said Dean Funes, "having been set up on immense plains, on which it was not easy to confine the herds within fixed limits, it sometimes happened that the animals went vast distances in search of water or pasture, and ended by being regarded as wild and ownerless," When D'Azara wants to show that the ranches of Paraguay are superior to those of Buenos Aires, he is content to say that there the animals are tamer (mansos). With the wild animal (alzado) is contrasted the de rodeo animal: that is to say, the cattle which are rounded up periodically in the centre of the ranch to be taken to the pasture where they must live (aquerenciar). It is the difficulty of preventing the dispersal of the herd that fixes the price of the rincones (surrounded by inundated areas) of Corrientes, in which the animals are captives.
MacKann's description of pastoral life in the Buenos Aires province in the middle of the nineteenth century give us a very clear impression of the stage of transition between exploiting the natural increase of a herd that multiplies without man's intervention, and breeding in the strict sense. The value of a horse in the former case is almost exclusively the cost of breaking it in. The breeder is actually anxious when he sees his horses increase, as he fears he may not have the resources for breaking them in. The most formidable of the dangers that threatened the feeble discipline of the herd was drought. That in the year 1827 was a disaster. The animals left the ranches in a body to go southward, where they mixed.[89]