Pliny: Natural History, Vol. V

18 The same ratio that makes a north-east wind more useful than a south-west wind also prefers inland regions to maritime ones—since they are generally colder—and mountainous regions to plains, and nocturnal rains to daily ones: crops enjoy the water more when the sun does not immediately take it away.

19 The theory of the location of vineyards and trees referring to the trees upon which vines are trained is connected to this, specifically which way they should face. Virgil condemned their being planted looking west, but some have preferred that aspect to an easterly position, while most authorities, I notice, approve the south; and I do not think that any hard and fast rule can be laid down on this point—skilled attention must be paid to the nature of the soil, the character of the locality, and the features of the particular climate.

20 In Africa, for vineyards to face south is bad for the vine and also unhealthy for the grower, because the country itself lies under the southern quarter of the sky, and consequently he who there chooses a westerly or northern aspect for planting will achieve the best blending of soil with climate. When Virgil condemns a western aspect, there seems no doubt that he condemns a northern aspect also; although in Italy below the Alps it has generally been experienced that no vineyards bear better than those so situated.

21 The wind also forms a great consideration. In the province of Narbonne, and in Liguria and part of Tuscany, it is thought to be a mistake to plant vines

in a position directly facing a west-north-west wind, but at the same time to be a wise arrangement to let them catch the wind from that quarter sideways, because it moderates the heat of summer in those regions, although it usually blows with such violence as to carry away the roofs of houses. Some people make the question of aspect depend on the nature of the soil, letting vines planted in dry situations face east and north, and those in a damp one south. Moreover, they borrow rules from the vines themselves, by planting early varieties in cold situations, so that their ripening may come before the cold weather, and fruit-trees and vines that dislike dew, with an eastern aspect, so that the sun may carry off the moisture at once, but those that like dew, facing west or even north, so that they may enjoy it for a longer time.

Effects of aspect on vines.

Georgics ii. 298.

But the rest, virtually following Nature's system, have recommended that vines and trees should be placed so as to face north-east; and Democritus is of opinion that the fruit so grown also has more scent. We have dealt in Book Two with positions facing north-east and the other quarters, and we shall give more meteorological details in the next Book. In the meantime a clear test of the healthiness of the aspect seems to lie in the fact that trees facing south are always the first to shed their leaves. A similar influence also operates in maritime districts: sea breezes are injurious in some places, while at the same time in most places they encourage growth; and some plants like having a distant view of the sea but are not benefited by being moved nearer to its saline exhalations. A similar principle applies also to rivers and marshes: they shrivel up vegetation by their mists or else they serve to cool excessively hot districts.