} { (_a_) Fruit spurs or
} {
1. High trunk: } { (_b_) Half-long canes and renewal
} { spurs or
2. Medium trunk: } with {
} { (_c_) Fruit canes and renewal
3. Low trunk: } { spurs; canes vertical
} { or bowed.

B. HEAD PRUNING: FAN-SHAPED; TRELLISED

1. High trunk: Fruit canes and renewal spurs; canes descending.

2. Medium trunk: Fruit canes and renewal spurs; canes horizontal or
ascending.

C. CORDON PRUNING

1. Vertical: Spur; half-long; cane.

2. Horizontal-unilateral: Spur; half-long; cane.

3. Horizontal-bilateral: Spur; half-long; cane.

All possible combinations indicated by this table represent 24
variations. Some of these combinations, however, are not used and some
are rare. The most common are shown in Figs. 23, 24, 25, 26 and 27.

Figure 23 B represents a headed, vase-formed vine, with a medium trunk
and short fruit spurs. This is the most common system used in all
parts of California and is suited for all small growing vines which
bear on the lower buds, for most wine grapes and for Muscats. The unit
of pruning in this case is a fruit spur of 1, 2, or 3 internodes,
according to the vigor of the variety and of the individual cane.

Figure 23 A differs from 23 B only in the higher trunk and longer
arms. It is commonly used for Tokay and other large growing
varieties, especially when growing in rich soil and when planted far
apart.

[Illustration: FIG. 23. Forms of head pruning: _A_, spur pruning with
high trunk; _B_, spur pruning with medium trunk; _C_, half-long with
medium trunk.]

Figure 23 C has the same form of body as A and B, except that the arms
are somewhat less numerous. The unit of pruning is a short fruit cane
of four to five internodes, accompanied by a renewal spur of one
internode. It is suited for vigorous table grapes, which do not bear
well on short spurs. It is used especially for the Cornichon and
Malaga in rich soil. This is a difficult system to keep in good shape
owing to the tendency for all the vigor to go to the growth on the
ends of the fruit canes. It is difficult to obtain vigorous canes on
the renewal spurs. Occasional short pruning is usually necessary to
keep the vines in proper shape.

Figure 24 A is similar to 23 C in form, but the number of arms is
still further reduced to 2, 3,