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AG-396 |
Knives
Grafting and budding knives are designed specifically for these
purposes and should not be used for carving and whittling wood. They
are available in either left- or right-handed models. The blade is
beveled on only one side, unlike conventional knives, which have
blades that bevel on both sides down to the cutting edge. Grafting
and budding knives must be kept razor sharp so they will cut
smoothly.
Pruning and Lopping Shears
Pruning and lopping shears should be the scissors or sliding blade
type rather than the blade and anvil type. If used to harvest scion
wood or budsticks, blade and anvil pruner will crush plant tissue. As
with knives, pruning and lopping shears should be kept razor sharp to
give clean, close cuts.
Grafting Tools
A special device known as a grafting tool has been designed for
making the cleft graft. It is used when the rootstock's diameter is
greater than 1 inch. The wedge-shaped blade is used to split the
stock, and the flat pick opens the cleft so that the scions can be
inserted. Once in place, the flat pick is removed and the cleft comes
together to hold the scions in position.
Wax Melter
Wax melters are used to heat the wax for sealing graft and bud
junctions. They are usually made by modifying kerosene lanterns. The
chimney is replaced by a small tin pot that serves as a receptacle
for the wax. When the flame is kept low, the wax is melted without
burning and can be kept at a suitable temperature.
The specialized terms listed here are often used in discussing
grafting and budding. The drawings in Figures 19 through 22 will help
in understanding these terms.
Adventitious buds - buds that can produce roots or shoots at
an unusual location on the plant if environmental conditions are
favorable.
Bark - all tissues lying outward from the vascular
cambium.
Bud - an immature or embryonic shoot, flower, or
inflorescence.
Budding rubber - a strip of pliable rubber 3/16 to 3/8 inch
wide by 4 to 8 inches long and 0.01 inch thick used to hold a bud in
proper position until the plant tissue has knitted together.
Callus - undifferentiated (parenchyma) tissue formed at a
wounded surface.
Cambium - a thin layer of living cells between the xylem
(outer sapwood) and phloem (inner bark) that is responsible for
secondary growth. Because cambium cells divide and make new cells,
the cambia of two different but related plant will grow together if
they are fixed and held firmly in contact.
Compatible - plant parts (scion and rootstock) that are
capable of forming a permanent union when grafted together.
Double-worked plant - a plant that has been grafted twice,
usually to overcome incompatibility between scion and rootstock; it
consists of a rootstock, interstock, and scion.
Graft - a finished plant that comes from joining a scion and a
rootstock.
Graft or bud union - the junction between a scion or bud and
its supporting rootstock.
Grafting paint - A mixture used like warm grafting wax to
cover wounds and prevent drying. It requires no heating before use
and dries to a moisture-proof seal when exposed to air. Unlike
conventional paints, it does not damage plant tissue.
Grafting strip - a rubber strip used to hold scions in place
until knitting has occured. Grafting strips are thicker and less
pliable than budding rubber.
Grafting twine - treated jute or raffia used to wrap graft
junctions to keep scions in place and cambia properly aligned.
Incompatible - plants whose parts will not form a permanent
union when grafted together.
lnterstock - an intermediate plant part that is cornpatible
with both the scion and the rootstock. Used in cases where the scion
and rootstock are not directly compatible with each other or where
additional dwarfing and cold or disease resistance is desired.
Parafilm - registered tradename for a nonsticky, selfadhering
parafin film. Can be stretched over a bud or graft to hold the bud or
scion in position as well as to seal the junction. Used in place of a
rubber strip or twine.
Polarity - a condition where stems grow shoots at the apical
or terminal end and roots at the basal end.
Raffia - One of several materials available for securing
scions or buds to the rootstock, A natural fiber from the fronds of
the raphia plam, raffia is one of the oldest materials in use. It
should be graded for uniform size and length and moistened just
before use to make it pliable.
Rootstock - the portion of a grafted plant that has (or will
develop) the root system onto which the scion is grafted.
Scion - a plant part that is grafted onto the interstock or
the rootstock. The scion usually has two or more buds.
Single-worked plant - a plant that has been grafted once; it
consists of a rootstock and a scion.
Standard - a single-stemmed understock used for the production
of weeping forms of woody plants. One or more scions are usually
grafted relatively high on the understock (2 to 6 feet).
Top-worked plant - an established tree or mature plant whose
upper portion has been removed back to the main limbs or trunk and
then grafted with new scions.
Understock - same as rootstock.
Union - the point where the scion and rootstock are
joined.
Warm grafting wax - a mixture, usually consisting or beeswax,
resin, and tallow plus a fungicide, that is applied warm over a bud
or graft junction to prevent drying and to serve as a topical
dressing.
