From Aggie Horticulture, Texas A&M AgriLife Extension Service,
Texas A&M University System
Publication from Aggie Horticulture®
T or Shield Budding
T budding or shield budding is a special grafting technique in which
the scion piece is reduced to a single bud. As with other techniques of
asexual propagation, the resulting plants are clones (genetically
identical plants reproduced from one individual entirely by vegetative
means). The plant being propagated (represented by the bud) is referred
to as the scion, while the plant being grafted onto is referred to as
the rootstock, or simply stock. A small branch with several buds
suitable for T budding on it is often called a bud stick.
Successful T budding requires that the scion material have
fully-formed, mature, dormant buds, and that the rootstock be in a
condition of active growth such that the "bark is slipping". This means
that the vascular cambium is actively growing, and the bark can be
peeled easily from the stock piece with little damage. T budding can be
performed on certain fruit trees (peaches, for example) in June using
cold stored budsticks and field grown seedling rootstocks. Many
deciduous trees are budded in late July or early August after the
current seasons buds have developed fully and are dormant using field
grown seedlings that have slipping bark.
Bud sticks having plump, healthy buds are suitable scions. These
budsticks should be on branches that exhibited good growth during the
current season, rather than ones from the interior of trees that have
slender stems and closely spaced, small buds. Thick water sprouts that
grew very vigorously are often poor scions. Leaf blades are clipped
from the budsticks, leaving the petiole intact. This leaves a
convenient "handle" for holding the bud while it is cut from the
The bud and a small sliver of the wood underneath it are cut from the
budstick using an upward slicing motion. The cut should begin about 1/2
to 3/4 inch below the bud, and should go deep enough into the wood so
that when the cut is finished about 1/2 to 3/4 above the bud, the bark
and a small sliver of wood are cut off. A perpendicular cut across the
top of the upward cut will separate it from the bud stick.
Budding knives should be kept very sharp, so that as little damage as
possible is done to the bud. Dull knives strip and tear the wood,
leaving cuts that do not heal properly. Buds must be cut from the bud
stick just prior to grafting, otherwise they will dry out. Some
grafters put the bud in their mouth for the time between when it is
removed from the stick and when it is grafted in place, but this
practice is not recommended. Speed in grafting is a more suitable
Some grafters make a downward cut as the second cut to remove the bud
from the budstick. This works well as long as it does not result in too
much of the underlying wood being removed with the bud.
A vertical cut is made on the stem of the root stock. The cut should be
deep enough to insure that the bark will separate at the cambium.
The "T is then crossed." That is, a perpendicular cut is made at the
upper end of the vertical cut. In areas with heavy rainfall during the
grafting season, or in species in which the rootstock is likely to
"bleed" heavily, an upside down, or inverted T bud can be used to
prevent water or sap from pooling in the graft.
The bark is carefully slipped from the stem of the rootstock exposing a
"pocket" into which the bud shield can be placed. Care should be taken
not to tear the flaps of bark in the process of spreading them.
If the bark does not slip easily, this indicates that the stock is not
in active growth and the process should be conducted later when active
growth has resumed.
An alternative method for budding which does not require the bark to
slip is the technique of chip budding in which the bud is cut out with
a "chip" of the underlying wood. This requires that a chip of
corresponding size be cut out of the stock piece in order to align the
cambia for proper graft healing.
The bud shield is carefully slipped in between the bark flaps. The top
of the bark strip on the bud shield is trimmed to fit tightly against
the horizontal cut (the cross of the T) so that the bud fits within the
The bark flaps are held tightly against the bud as they are wrapped
with a budding rubber, grafting tape or other suitable closure. This
closure must either breakdown by weathering (as budding rubbers do), or
must be removed in 2 to 3 weeks after the union has healed. If the
material does not break down, it will girdle the rootstock.
After the union has healed, the upper part of the rootstock plant can
be cut away to force the bud to grow (as would be the case for June
budding). If the grafting is done in the late summer, the bud likely
will need to overwinter prior to resuming growth. In this case, the
upper portion of the rootstock is usually removed during the dormant
season, either in late winter or early spring.
After the upper portion of the rootstock is removed, the scion bud
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