eyards are laid out for the most part after accepted patterns for
each of the great grape regions of America. The vines are always
planted in rectangles, usually at a less distance apart in the rows
than the rows are from each other, but sometimes in squares. Pride in
appearance and convenience in vineyard operations make perfect
alignment imperative. Many varieties of grapes, especially of American
species, are partially self-sterile, so that some varieties must have
others interplanted with them for cross-pollination. This is usually
done by setting alternate rows of the variety to be pollinated and the
cross-pollinator. All self-fertile varieties are set in solid blocks
because of convenience in harvesting.

_Direction of rows._

Some grape-growers attach considerable importance to the direction in
which rows run, holding either that the full blaze of the sun at
mid-day is desirable for vine, soil and fruit, or that it is
detrimental. Those who desire to provide fullest exposure to the sun
plant rows east and west when the distance between vines is less than
the distance between rows; north and south when vines are farther
apart in the row than the rows are from each other. When shade seems
more desirable, these directions are reversed. Most often, however,
the rows are laid out in accordance with the shape of the vineyard;
or, if the land is hilly, the rows follow the contour of the
declivities to prevent soil erosion by heavy rains.

_Alleys._

For convenience in vineyard operations, especially spraying and
harvesting, there should always be alleys through a vineyard. On hilly
lands, the alleys are located to secure ease in hauling; on level
lands they are usually arranged to cut the vineyards into blocks twice
as long as wide. An alley is usually made by leaving out a row of
vines. Many vineyards are laid out with rows far enough apart so that
alleys are not needed.

_Distances between rows and plants._

There are great variations in the distances between rows and plants in
different regions, and distances vary somewhat in any one region.
Distances are influenced by the following considerations: Rich soils
and large vigorous varieties require greater distances than poor soils
and less vigorous varieties; sometimes, however, it is necessary to
crowd a variety in the vineyard so that by reducing its vigor
fruitfulness may be promoted. Usually the warmer the climate, or the
exposure, the greater should be the