n it is
disseminated in the air, as the physicist Anaxagoras holds, or is
distributed over the land by the surface water, as Theophrastus
maintains. The seeds which the farmer can see should be studied with
the greatest care. There are some varieties, like that of the cypress,
which are so small as to be almost invisible, for those nuts which the
cypress bears, that look like little balls covered with bark, are not
the seed but contain it. Nature gave the principle of germination to
seed, the rest of agriculture was left for the experience of man to
discover, for in the beginning before the interference of man plants
were generated before they were sown, afterwards those seeds which
were collected by man from the original plants did not generate until
after they had been sown.

Seed should be examined to ascertain that it is not sterile by age,
that it is clean, particularly that it is not adulterated with other
varieties of similar appearances: for age has such effect upon seed as
in some respects to change its very nature, thus it is said that rape
will grow from old cabbage seed, and vice versa.[90]

_b. Transplanting_

In respect of transplanting, care should be taken that it is
done neither too soon nor too late. The fit time, according to
Theophrastus, is spring and autumn and midsummer, but the same rule
will not apply in all places and to all kinds of plants: for in dry
and thin clay soil, which has little natural moisture, the wet spring
is the time, but in a rich and fat soil it is safe to transplant in
autumn. Some limit the practice of transplanting to a period of thirty
days.

_c. Cuttage_

In respect of cuttage, which consists in planting in the ground a live
cutting from a tree, it behooves you especially to see that this is
done at the proper time, which is before the tree has begun to bud or
bloom: that you take off the cutting carefully rather than break
it from the parent tree, because the cutting will be more firmly
established in proportion as it has a broad footing which can readily
put out roots: and that it is planted promptly before the sap dries
out of it.

In propagating olives select a truncheon of new grown wood about
a foot in length and the same size at each end: some call these
_clavolae_ and others call them _taleae_.

_d. Graftage_

In respect of graftage, which consists in transferring growing wood
from one tree to another, care must be taken in selecting the tree
fr