g one or more canes, cut to
the desired number of buds, to supply bearing shoots. By this method
the most of the bearing wood is removed each year, new canes taking
the place of the old. These renewal canes may be taken either from the
head of the vine or from the ground, though the latter is little used
except where vines must be laid down for winter protection. Canes may
be renewed indefinitely, if care is exercised in keeping the stubs
short, without enlarging the head from which the canes are taken out
of proportion to the size of the trunk. Renewing by canes is a more
common method than renewal by spurs, as will be found in the
discussion of methods of training.

[Illustration: FIG. 13. Vine ready for pruning; _i_, the stem; _g_,
arms; _d_, canes; _s_, shoots; _b_, spurs. The faint lines near the
bases of the canes indicate the points where they should be pruned off
in the winter, leaving spurs for the production of shoots the
following season.]

_Spur renewal._

In renewing by spurs, a permanent arm is established to right and left
on the canes. Shoots on this arm are not permitted to remain as canes
but are cut back to spurs in the dormant pruning. Two buds are left at
this pruning, both of which will produce bearing shoots; the lower
one, however, is not suffered to do so but is kept to furnish the spur
for the next season. The shoot from the upper bud is cut away
entirely. When this process is carried on from year to year, the spurs
become longer and longer until they become unwieldy. Occasionally,
however, happy chance permits the selection of a shoot on the old wood
for a new spur. Failing in this, a new arm must be laid down and the
spurring goes on as before. The objections to renewing by spurs are:
it is often difficult to replace spurs with new wood, and the bearing
portion of the vine gets farther and farther from the trunk. For these
reasons, spur-renewing is generally in disfavor with commercial
grape-growers, though it is still used in one or two prominent
methods of training, as will be discovered in this discussion. Figure
13 shows a vine ready for pruning.

THE WORK OF PRUNING

The pruner may take his choice between several styles of hand
pruning-shears with which to do his work. The knife is seldom used
except in summer-pruning, and here, more often, the shoots are broken
out or pinched out. In winter-pruning, the cane is cut an inch or
thereabout beyond the last bud it is desired to leav