cions may be inserted as the original cutting and not as the new
growth. The roots, for convenience in handling, are cut back to an
inch or thereabouts in length.

_The callusing bed._

If bench grafts are planted at once in the nursery, most of them fail.
They are, therefore, stratified in a callusing bed where moisture and
temperature can be controlled. Bioletti describes a callusing bed and
its use as follows:[6]

"This callusing bed is usually a pile of clean sand placed on the
south side of a wall or building and surrounded by a board partition
where there is no possibility of its becoming too wet by the flow of
water from a higher level or from an overhanging roof. It should be
protected, if necessary, by a surrounding ditch. It should be
furnished with a removable cover of canvas or boards to protect it
from rain and to enable the temperature to be controlled by the
admission or exclusion of the sun's rays. A water-proof wagon-cover,
black on one side and white on the other, is excellent for this
purpose.

"The bottom of the callusing bed is first covered with 2 or 3 inches
of sand. The bundles of grafts are then placed in a row along one end
of the bed, and sand well filled in around them. The bundles should be
placed in a slightly inclined position with the scions uppermost, and
the sand should be dry enough so that it sifts in between the grafts
in the bundle. The bundles of grafts are then covered up completely
with sand, leaving it at least 2 inches deep above the top of the
scion. Another row is then placed in the same manner until the bed is
full. Finally a layer of 2 or 3 inches of moss or straw is placed over
all.

"In the callusing bed we should endeavor to hasten and perfect the
union of stock and scion as much as possible while delaying the
starting of the buds and the emission of the roots. The latter
processes require more moisture than the formation of healing tissue,
therefore the sand should be kept comparatively dry. Between 5 and 10
per cent of water in the sand is sufficient. The purer the sand the
less water is necessary. There should be a little more moisture
present than in the sand used for keeping the cuttings over winter.
Too much moisture will stimulate the emission of roots and starting of
buds without aiding the callus formation.

"All the vital processes progress more rapidly when the cuttings are
kept warm. To delay them, therefore, we keep the sand cool, and to
hasten the