Thus there are as many methods of cultivating the vine as there are
kinds of soil. For where the land is wet the vine must be trained high
because when wine is being made and matured on the vine, it needs sun,
not water--as when it is in the cup! For this reason it was, I think,
that first the vine was made to grow on trees.

_Of the different kinds of soil_

IX. It is expedient then, as I was saying, to study each kind of soil
to determine for what it is, and for what it is not, suitable. The
word _terra_ is used in three senses: general, particular and mixed.
It is a general designation when we speak of the orb of the earth, the
land of Italy or any other country. In this designation is included
rock and sand and other such things. In the second place, _terra_ is
referred to particularly when it is spoken of without qualification or
epithet. In the third place, which is the mixed sense, when one speaks
of _terra_ as soil--that in which seeds are sown and developed; as for
example, clay soil or rocky soil or others. In this sense there are as
many kinds of earth as there are when one speaks of it in the general
sense, on account of the mixtures of substances in it in varying
quantities which make it of different heart and strength, such as
rock, marble, sand, loam, clay, red ochre, dust, chalk, gravel,
carbuncle (which is a condition of soil formed by the burning of roots
in the intense heat of the sun); from which each kind of soil is
called by a particular name, in accordance with the substances of
which it is composed, as a chalky soil, a gravelly soil, or what ever
else may be its distinguishing quality. And as there are different
varieties of soil so each variety may be subdivided according to
its quality, as, for example, a rocky soil is either very rocky,
moderately rocky or hardly rocky at all. So three grades may be made
of other mixed soils. In turn each of these three grades has three
qualities: some are very wet, some very dry, some moderate, These
distinctions are of the greatest importance in respect of the crops,
for the skilled husbandman plants spelt rather than wheat in wet
land, and on dry land barley rather than spelt, in medium land both.
Furthermore there are still more subtle distinctions to be made
in respect of all these kinds of soil, as for example it must be
considered in respect of loam, whether it is white loam or red loam,
because white loam is unfit for nursery beds, while red loam i