Connected, too, with this subject is the question of the best situation for planting vines, and the trees which support them. Virgil[2825] condemns a western aspect, while there are some persons, again, who prefer it to an easterly one: I find, however, that most authors approve of the south, though I do not think that any abstract precepts[2826] can be given in relation to the point. The most careful attention on the part of the cultivator ought to be paid to the nature of the soil, the character of the locality, and the respective influences of climate. The method of giving to the vine a southern aspect, as practised in Africa and * * * * is injurious to the tree, as well as unhealthy for the cultivator, from the very circumstance that the country itself lies under a southern meridian: hence it is, that he who selects for his plants there a western or a northerly aspect, will combine on the most advantageous terms the benefits of soil with those of climate. When Virgil condemns a western aspect, there can be no doubt that he includes in his censure a northern aspect as well: and yet, in Cisalpine Italy, where most of the vineyards have an aspect to the north, it has been found by experience that there are none that are more prolific.
The winds are also a very important consideration. In the provinces of Gallia Narbonensis, and in Liguria and part of Etruria, it is considered a proof of great want of skill to plant the vine on a site that lies in the teeth of the wind Circius,[2827] while, on the other hand, it is a mark of prudence to catch its breezes in an oblique direction; it is this wind, in fact, that modifies the heat in those countries, though at the same time it is usually so violent, as to sweep away the roofs of the houses.
(3.) There are some persons who employ a method of making the question of weather dependent upon the nature of the soil; thus in the case of a vineyard, for instance, in a dry locality, they give it an eastern or a northern aspect; but where it is planted on a humid site, it is made to face the south. From the varieties of the vine also, they borrow various modifications in reference to site; taking care to plant the early vine in a cold locality, in order that the fruit may ripen before the frosts come on; while such fruit trees and vines as have an antipathy to dews are exposed to the east, that the sun may carry off their humidity at the earliest moment. On the other hand, such as manifest a partiality to dews are planted with a western or even a northern aspect, to give them an opportunity of enjoying them all the longer. Others, again, borrowing their notions pretty nearly from Nature, have recommended that vines and trees should be planted facing the north-east; indeed Democritus is of opinion, that by so doing the fruit will be all the more odoriferous.
(4.) We have already spoken, in the Second Book,[2828] of the points of the north-east and other winds, and shall have occasion in the succeeding one to make mention of several more of the heavenly phænomena. In the mean time, however, we may observe that it would appear to be a manifest proof of the salubrity of a north-east site, that the leaves are always the first to fall in the trees that have an aspect towards the south.[2829] A similar reason exists, too, in the maritime districts; in certain localities the sea breezes are detrimental, though in most they are nutritious. For some plants, again, it is pleasant to behold the sea at a distance, while at the same time they will gain nothing by approaching closer to its saline exhalations. The same, too, is the influence exercised by rivers and lakes; they will either scorch the vegetation by the fogs they emit, or else modify by their coolness the excess of heat. We have already mentioned[2830] the plants that thrive in the shade, and in the cold even; but in all these matters experience will be found the best of guides.
CHAP. 3.—WHAT SOILS ARE TO BE CONSIDERED THE BEST.
Next after the influences of the heavens, we have to treat of those of the earth, a task that is in no way more easy than the previous one. It is but rarely that the same soil is found suited to trees as well as corn: indeed, the black[2831] earth which prevails in Campania is not everywhere found suited to the vine, nor yet that which emits light exhalations, or the red[2832] soil that has been so highly praised by many. The cretaceous earth that is found in the territory of Alba Pompeia, and an argillaceous soil, are preferred to all others for the vine, although, too, they are remarkably rich, a quality that is generally looked upon as not suited to that plant. On the other hand, again, the white sand of the district of Ticinum, the black sand of many other places, and the red sand as well, even though mixed with a rich earth, will prove unproductive.
The very signs, also, from which we form our judgment are often very deceptive; a soil that is adorned with tall and graceful trees is not always a favourable one, except, of course, for those trees. What tree, in fact, is there that is taller than the fir? and yet what other plant could possibly exist in the same spot? Nor ought we always to look upon verdant pastures as so many proofs of richness of soil; for what is there that enjoys a greater renown than the pastures of Germany? and yet they consist of nothing but a very thin layer of turf, with sand immediately beneath. Nor yet is the soil which produces herbage[2833] of large growth always to be looked upon as humid; no, by Hercules! no more than a soil is to be looked upon as unctuous and rich, which adheres to the fingers—a thing that is proved in the case of the argillaceous earths.[2834] The earth when thrown back into the hole from which it has just been dug will never[2835] fill it, so that it is quite impossible by that method to form any opinion as to its density or thinness. It is the fact, too, that every[2836] soil, without exception, will cover iron with rust. Nor yet can we determine[2837] the heaviness or lightness of soils in relation to any fixed and ascertained weight: for what are we to understand as the standard weight of earth? A soil, too, that is formed from the alluvion[2838] of rivers is not always to be recommended, for there are some crops that decay all the sooner in a watery soil; indeed, those soils even of this description which are highly esteemed, are never found to be long good for any kind of vegetation but the willow.
Among other proofs of the goodness of soil, is the comparative thickness of the stem in corn. In Laborium, a famous champaign country of Campania, the stalk is of such remarkable thickness, that it may be used even to supply the place of wood:[2839] and yet this very soil, from the difficulty that is everywhere experienced in cultivating it, and the labour required in working it, may be almost said to give the husbandman more trouble by its good qualities than it could possibly have done by reason of any defects. The soil, too, that is generally known as charcoal earth, appears susceptible of being improved by being planted with a poor meagre vine: and tufa,[2840] which is naturally rough and friable, we find recommended by some authors. Virgil,[2841] too, does not condemn for the vine a soil which produces fern:[2842] while a salted earth[2843] is thought to be much better entrusted with the growth of vegetation than any other, from the fact of its being comparatively safe from noxious insects breeding there. Declivities, too, are far from unproductive, if a person only knows how to dig them properly; and it is not all[2844] champaign spots that are less accessible to the sun and wind than is necessary for their benefit. We have already[2845] alluded to the fact, that there are certain vines which find nutriment in hoar frosts and fogs.
In every subject there are certain deep and recondite secrets, which it is left to the intelligence of each to penetrate. Do we not, for instance, find it the fact, that soils which have long offered opportunities for a sound judgment being formed on their qualities have become totally altered? In the vicinity of Larissa, in Thessaly, a lake was drained;[2846] and the consequence was, that the district became much colder, and the olive-trees which had formerly borne fruit now ceased to bear. When a channel was cut for the Hebrus, near the town of Ænos, the place was sensible of its nearer approach, in finding its vines frost-bitten, a thing that had never happened before; in the vicinity, too, of Philippi, the country having been drained for cultivation, the nature of the climate became entirely altered. In the territory of Syracuse, a husbandman, who was a stranger to the place, cleared the soil of all the stones, and the consequence was, that he lost his crops from the accumulation of mud; so that at last he was obliged to carry the stones back again. In Syria again, the plough-share which they use is narrow, and the furrows are but very superficial, there being a rock beneath the soil that in summer scorches up the seeds.