The oases of Cuyo are like the small oases of the north-west as regards the function of those who are engaged in the administration of irrigation. The water-laws give the provincial functionaries general directions. Below them, however, to arrange the distribution of the water and the upkeep of the canals in detail, they have allowed to survive, and have merely regulated, certain primitive democratic organisms. At San Juan the superintendence of the irrigation is entrusted to elected municipal councils and the governor of the department. At Mendoza, the owners appoint a council of three delegates and an inspector for each canal, and these settle the annual budget of the canal, submit it to the provincial authorities, receive the taxes, carry out the necessary repairs, and so on. The great subdivision of property and the large number of electors make these little republics very lively; and they are very jealous of their autonomy.[37] [37] There are more than 6,000 owners at San Juan to 91,000 hectares, and more than 9,000 at Mendoza (zone of the rivers Mendoza and Tunuyan) to 130,000 hectares (statistics compiled in 1899). Even within the narrow limits of the Cuyo district the climatological conditions, which control the growth of the vine, are not everywhere the same. The opening of the vineyards varies by several weeks, according to the locality.[38] The northern slope of the cone, exposed to the sun and protected from the southern winds, is more precocious. Some districts, poorly sheltered from the southern winds, and very liable to have late frost, have not been planted with vines (district of the Tucuyan below San Carlos, to the south of Mendoza). Everywhere the dryness of the atmosphere causes the ripe grapes to remain long on the vine, so that the harvest may last two months or more without any harm. It thus requires a relatively small supplement of manual labour, and does not necessitate seasonal migrations. The length of the harvest, moreover, facilitates the trade in grapes, which is one of the special features of the Argentine vine-industry. [38] The difference is much greater at a distance from the Cuyo province. Catamarca, which specializes in the production of grapes for the table, is invaded by buyers from Buenos Aires, and begins to send grapes in December, two full months before the harvest begins in Mendoza.