The Sierra de los Llanos in La Rioja is another centre for extensive breeding. From the railway, which follows the range at some distance, between Chañar and Puntá de los Llanos, before it reaches La Rioja, no one would have the least suspicion of the importance and life of the region. It is, nevertheless, one of the main foci of Argentine history. It has proved a cradle of population and wealth. It was there that Quiroga and, later, the strange adventurer who was known by the nickname of the "Chacho" gathered the strength that enabled them to dominate part of Argentina. Colonization is even older here than in the Chaco Salteño. It occupied two distinct periods, separated by a long interval. At first it advanced from north to south, passing round the foot of the Sierra. It is marked by a line of springs, poor but permanent, the waters of which are absorbed as soon as they flow down to the porous alluvial beds of the plain. They appear much in the names of the district—agüitas, aguaditas, and so on, abound. The road from La Rioja to San Luis passed these springs, and some population grew up about them. Thus the two sides of the range—the costa baja in the east and the costa alta in the west—became inhabited. The estate of Facundo is one of these aguaditas of the costa alta.

The two costas form the historic territory of the Llanos. It was from there that colonization swarmed over the plain long afterwards. This expansive movement began about 1850; that is to say, at a time when the breeders enjoyed comparative peace and security, and especially when the invernadas of San Juan and Mendoza were developed, together with the export of cattle to the agricultural provinces of Chile. The price of stock rose, and the unoccupied land became of value. The occupation and exploitation of the plain was the work of the last two generations. They pushed on to the very edge of the salt lakes, leaving no vacant space. The travesias which surrounded the narrow inhabited zone of the costas were filled with life. The Sierra and its two costas are no longer an oasis in the desert, as they were in the time of Sarmiento; though they still differ from the remainder of the pastoral zone in the density of their population and the variety of their resources.

The early date of the colonization may be traced in a special system of tenure, though this is also found in parts of the provinces of Catamarca and Santiago del Estero. On the plain the right of ownership was obtained in the nineteenth century by purchase or by concessions of public lands which belonged to the provincial Government. They were allotted in very large estates, and these, intact or broken up, are the actual ranches. In approaching the foot of the range one passes estates in the mercedes. The name indicates concessions that date from the colonial epoch, and they are, in all parts of South America that were early colonized, the source of land-ownership. But what is peculiar to the mercedes of the Llanos is that they have never been divided amongst the heirs of the first owner.[31] Sometimes the number of co-proprietors is small. They are conscious of their relationship to each other and know the value of the rights of each. The merced is in that case only an undivided property held in common. Sometimes, however, the numbers of comuneros is so great that they have lost count of the exact share of the merced which belongs to each of them. The merced feeds a whole population, legitimate heirs and usurpers mixed together. In these cases it is a real communal property, and one might compare it, in spite of its different origin, with the Indian communities which exist in Argentine territory as well as that of most of the other Andean States.

The economy of the Llanos is less simple than that of the Chaco Salteño. There is agriculture as well as breeding. There is not much rain, and it is confined to the summer months. The mean rainfall is, no doubt, higher than what we find at La Rioja (about 30 centimetres), but it is not good enough to dispense with irrigation. The aguadas, springs and brooks at the foot of the range, are the only provision of permanent water, and it is very limited. The oases watered by these springs and brooks cover only a few acres at the foot of the steep cliffs of the range. It has not been possible to cultivate the land far from the mountains. At Chamical a trench that was made to convey water to the railway dried up. All that can be done is to follow for a few miles with a line of wells a subterranean stream of fresh and not very deep water. At Bella Vista a comunero has dug an acequia several miles long, and he sells the water at a rate of five piastres for forty-eight hours. But when it reaches the end of the acequia, it is lost between the trench and the field to which they would conduct it. At Ulapes, though it is one of the chief centres, it takes the full outflow of the spring during sixteen hours to irrigate one cuadra (a little over two acres), and each man's "turn" is for seventeen days. The entire oasis measures about fifty acres. At Olta the thin stream of water is surrounded by so many cupidities that the "turn" comes only every fifty-eight days, so that each field has to live fifty-eight days on one watering. At Catuna where a trickle of brackish water is eagerly collected at the foot of a dejection-cone, the water-right is regulated by an arrangement of turns that covers ninety days, so that plants die of thirst in the interval. The plots vary according to the quantity, quality, and regularity of the water. The orange-tree is the most exacting, the fig the most tenacious, of the trees. The poorest oases consist only of a few gardens of dusty fig-trees.

However small it is, the oasis always stands for a rudiment of communal life, a poblado, a centre round which life is organized in this pastoral, anarchic, amorphous world. Land that has a water-right is regarded as detached from the merced and never remains undivided.

Besides these properly irrigated lands there are the bañados: cultivated plots in the hollows, where the moisture left by the storms is concentrated and preserved. These are much more extensive, and they are very irregularly distributed. Inequalities of the alluvial ground that almost escape the eye are sufficient to direct the streaming of the water after rain, and it is quickly absorbed. Man assists nature as well as he can, and one sees everywhere tiny ridges of earth across the paths, for the purpose of diverting the water to the plots. These are the tomas. When you follow a toma downward, you see it after a time pass under a hedge of dry thorn, and this encloses a field, a cerco. The crops have to be jealously guarded against the cattle which roam in the scrub. The cercos are sometimes so numerous that they give the impression of a regular agricultural district. Most of them are planted with maize. The maize harvest rarely fails in the summer, for it is then, on account of the regular rains, that the maize grows and ripens. When the ears have been gathered, the cattle are let into the cerco, as maize-straw is excellent fodder. But wheat also grows well in the bañados. Provided the year has had a few late showers, the wheat sown in autumn stands the winter drought more or less well, and ripens after the early rains, at the beginning of summer. The Llanos produce a hard wheat; it is not milled, but eaten, like rice, in the grain. There have been times when the Llanos have exported wheat. The census of 1888 gives the Department of General Belgrano, on the eastern slope of the Llanos, an area of 900 acres under maize and 1,900 under wheat. When the Chilecito railway was constructed, this wheat competed with that brought on mules from Jachal, in the mining district of the Famatina range. Like the gardens in the oases, the cercos may be divided, and they are the personal property of those who cultivate them.

Sowing and reaping are, however, mere episodes in the life of the Llanero. He is mainly occupied with cattle-breeding. The quality of the pasture differs considerably according to the nature of the soil and the good and bad character of the season. Sometimes it forms a thick carpet under the brushwood, but in other places it is poor and there is nothing but the leaves and pods of the algarroba. If the herd is too large, the grass will not grow again; the breeder recognizes at a glance the campo recargado—the field which has had its capacity overstrained. The pasture has to be carefully nursed. But the most urgent problem is to get a supply of water for the cattle. Round the Sierra the underground water is often fresh, and there are plenty of wells. Still, in order to avoid having to draw the water, they dig large trenches at suitable spots in the clay, and round these they arrange the earth that has been dug out, with an opening toward the hills to catch the water when it is raining. These are the represas. As in the case of the bañados, ridges of earth direct the stream to the represa. It is surrounded by a hedge as carefully as the field is. On the plain rain is rare, and the represas are usually the only reserve. They have to last the whole year; even two years if there is a particularly dry summer that prevents re-filling. Thus they become sometimes veritable lakes. From a distance you can see, above the top of the brushwood, the bald curve of the mound of beaten earth which encircles them. The water flows over it when there has been much rain. The mound is sometimes 4½ to 5½ yards high; as it is at Tello, between the Sierra d'Ulapes and the Sierra de los Llanos, where the San Juan coach used to change horses.

The represa is the real centre of the estate. The house is built near it, and guards the entrance. From early morning until dusk the cattle come to it, singly or in groups. The rancher admits them, lets them drink, and closes the gate behind them. If the thirsty cattle have not his mark and belong to a neighbour, he sends them to drink at their own represa; but he gives water to lost beasts, from a distance, whose owner will presently come for them. Near the represa is the enclosure (potrero) for calves that have just been born. The cows come there every morning, and they are milked for a few months to make cheese. Like the cerco, the represa is the personal property of the man who made it, or of one who has inherited it and sees to its upkeep.

The cattle of the Llanos move a good deal. There are certain irregular migrations, and others that are periodic or connected with the seasons. Everywhere on the fringe of the Sierra the cattle remain in the ravine and on the foot-hills during the winter. In the summer they return of themselves to their querencia on the plain. The irregular migrations are due to scarcity of water or pasture. Driven by hunger, the beasts travel a long distance of their own accord. They mingle with other herds, sometimes so far from the ranches where they were born that no one recognizes their mark. Sometimes, again, the rancher himself goes, when his represa is dry, to ask hospitality in some more favoured canton. He is fortunate if the drought has not been general; if part of the country has been spared and can offer a refuge.