sary to
prevent self-pollination. This first operation having been performed,
the cluster of grape-flowers must be tied securely in a bag to protect
it from foreign pollen which otherwise would surely be carried to the
stigma by insects. As soon as the stigma is ready to receive the
pollen, the bag is removed and pollen from the male parent is applied,
after which the bag is again put on the flower to remain until the
grapes are well set. By examining the stigmas in the flowers of
uncovered grapes, the operator can tell approximately whether the
covered stigma is ready to receive pollen. The time required after
covering depends, of course, on the age of the bud when emasculation
takes place. It is, by the way, best to delay emasculation until just
before the flowers open, but one must be certain that the anthers have
not discharged their pollen before the flower has been emasculated.

Emasculation is a simple operation. The essential organs of the
grape-flower are covered by a small cap; this in some grapes must be
removed before the anthers can be reached. In many native grapes,
however, the cap and the anthers may be removed at one stroke by the
operator. The best tool for this is a small pair of forceps. Each of
the blades of the forceps in working with native grapes should have a
sharp cutting surface, but with Vinifera sorts, where the cap must be
removed before the anthers can be reached, forcep blades with a flat
surface are best. There is, of course, some danger when the buds are
well developed that the pollen may be squeezed out and so reach the
stigma or adhere to the instrument and thus contaminate future
crosses. The first danger must be avoided carefully by the skill of
the operator, while the second is easily overcome by sterilizing the
forceps in alcohol. An effort should be made to fertilize as many of
the flowers in the cluster as possible, but success is not always
certain; when there is doubt, the uncertain flower should be removed
from the cluster.

The flower from which the pollen is to be taken must be protected from
wind and insects; otherwise pollen from another flower may be left on
it. Protection should be given by tying the flowers in a bag while
still in bud. There are various ways of obtaining pollen from ripe
anthers and applying it to the stigma of the flowers to be crossed.
The simplest is to crush the anthers, thus squeezing out the pollen,
after which, with a brush, scalpel or other i