BOOK XVII. I. S-ii. II
should grow for the poor. We will now therefore state in what manner it chiefly comes about that such a large revenue is derived from these trees, going on to set forth the genuine and perfect method of cultivation, and for that purpose we shall not treat of the commonly known facts and those which we observe to be established, but of uncertain and doubtful points on which practical conduct chiefly goes wrong; as it is not our plan to give careful attention to superfluities. But first of all we will speak about matters of climate and soil that concern all kinds of trees in common.
Effect of aspect and weather.II. Trees are specially fond of a north-easta aspect, wind in that quarter rendering their foliage denser and more abundant and their timber stronger. This is a point on which most people make a mistake, as the props in a vineyard ought not to be placed so as to shelter the stems from wind in that quarter, and this precaution should only be taken against a north wind. What is more, exposure to cold at the proper season contributes very greatly to the strength of the trees, and they bud best under those circumstances, as otherwise, if exposed to the caresses of the winds from the south-west, they languish, and especially when in blossom. In fact if the fall of the blossom is followed immediately by rain, the fruit is entirely ruined—so much so that almonds and pears lose their crop of fruit if the weather should be only cloudy or a south-west wind prevail. Rain at the rising of the Pleiadesb indeed is extremely unfavourable for the vine and the olive, because that is their fertilizing season; this is the four-day period that decides the fate of the olives, this is the critical point when a south wind brings the dirty clouds we spoke of. XVI. 109.Also cereals ripen worse on days when the wind is in the south-west, though they ripen faster.9