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[EarthNSky <erthnsky AT bellsouth.net>]

I found this online, created a document, and thought I would pass it on
here for anyone who might be interested.

Bev


Oklahoma Cooperative Extension Fact Sheets are also available on our
website at:
http://www.osuextra.com
Propagation of Fruit
and Nuts by Seed
B. Dean McCraw, Professor
Extension Tree Fruit and Pecan Specialist
Although most of the fruit and nut trees do not bear fruits true to
variety when propagated by seeds, seeds may need to be planted in order
to get the understock on which to propagate the wood of better
varieties. Certain treatments need to be given to most of the seeds in
order to get them to germinate.  In some cases, a hard seedcoat may
hinder germination.  One of the following three treatments will usually
make the seed-coats permeable to water: (1) soaking in sulfuric acid,
(2) soaking in hot water or immersing the seed for a short period in
boiling water, and (3) mechanical scarification.  Of all of the causes
of natural delay in seed germination, dormancy of the embryo is most
common. A seed with a dormant embryo must complete a process of
“after-ripening” before it acquires the ability to germinate.
After-ripening takes place only at the proper temperature and in the
presence of abundant supplies of moisture and air (oxygen). For most of
the native trees and shrubs in Oklahoma, an average temperature of 41°F
is favorable to after-ripening.  In practical handling of dormant seed,
after-ripening is done by “stratification,” i.e. by mixing the seed with
moist sand, sawdust, or peat moss. The latter, peat moss, is preferable
because it has a very large water-holding capacity, and yet while moist
(not wet), it does not interfere with aeration of the seed.
After being thoroughly mixed with the stratification medium, the seed is
placed in baskets, crates, jars, or any other convenient container. The
seed container is stored in a place where the temperature, through a
definite period of time, will be maintained within the range effective
in after-ripening.  Standard bushel and half-bushel baskets, glass jars,
and tin cans are very convenient. For the sake of reducing the chances
of infection, line the inside of a basket with clean paper before
placing stratified seed into it. Stratified seed should never be packed
tightly because this will interfere with good aeration.
After the mixture of seed and stratification medium is in a container,
it is advisable to put an additional layer (1/2 inch thick) of pure peat
moss, sand, or sawdust on the top of the mixture and to cover the
container with paper. This will help in keeping the seed moist
throughout the period of stratification.  Properly stratified and
well-covered seed kept at a low temperature should remain moist for at
least two or three months.  Large quantities of stratified seed can be
kept in a cold room or in a cellar. When neither of these is available,
the seed can be buried outdoors on the north side of a building.  Small
quantities of seed that are commonly handled by home gardeners can be
placed in small jars and kept in a refrigerator or icebox.
The length of the stratification period varies with seed of different
species. The recommendation made for each species is only an average and
not an exact, standard period.  For the seed of some species, fall
planting is a satisfactory substitute for stratification and saves time,
labor, and space in cold storage. For these species, fall planting is
effective if the seeds remain moist and are well protected from rodents
and if the temperature in the winter stays low for a sufficient length
of time.
Nuts
Hickories (Carya spp.) The seeds of most hickories are dormant,
requiring stratification for various periods of time.  Stratification
requirements depend on the species and, to some extent, on the origin of
the seed. The approximate stratification requirement of nuts of the most
common Oklahoma hickories is three months at 33°F to 50°F. Fall planting
of hickory nuts is used very successfully, provided that the nuts are
well protected against rodents and severe freeze.
Pecans (C. illionesis) The pecan differs from other hickory nuts in its
characteristics and requirements. It does not fall into dormancy but can
germinate at any time when conditions are favorable. Despite this
difference, pecan seed is commonly stratified or kept in cold storage at
high humidity through the winter and planted in the spring of the year.
This prevents the nut from becoming rancid and from losing its
viability. And at the same time, the possibility of the pecan
germinating out of season is excluded. If planted during the fall and
winter, the non-dormant pecan will usually germinate the following spring.
Black Walnuts (Juglans nigra) Black walnut, when ripened and shed from
the tree, is dormant. The seed coat, though extremely hard, permits the
kernel to absorb water rather freely. By the time the kernel
after-ripens and is ready to resume growth, the hard seed coat cracks
along the edges and, thus, presents no obstacle to the growing embryo.
Black walnut after-ripens in stratification at 33°F to 50°F in two or
three months. Many propagators prefer fall planting, but in Oklahoma the
winter temperature may not stay low enough for the sufficient length of
time.





Small Fruit
Blackberries (Rubus spp.) Blackberry seed, due to the dormancy of its
embryo, requires stratification at 33°F to 35°F before being planted.
The stratification requirement varies considerably with sometimes as
long as five to six months being necessary. The average is approximately
three months.  September is suggested as the best time for planting.
Treat dry seed with acid for about 30 minutes. Commer-cial varieties of
blackberries are commonly propagated by root cuttings or tip layering.
Grapes (Vitis spp.) Grape seed requires stratification at 37°F, varying
in length from 90 to 140 days.  Because of the great variation of grape
seedlings, seed cannot be relied upon to produce a vineyard of the
desired variety. Commercial varieties of grapes are propagated by
cuttings and grafting and sometimes by budding and layering.
Tree Fruits
Apple (Malus spp.) The seed of apple is used primarily for the
production of root-stocks, since apple varieties do not come true from
seed. The seed of apples is dormant and requires stratification at 34°F
to 40°F for a period of two to two and a half months for the completion
of after-ripening. From the time of its extraction from the fruit, the
seed should be kept continuously moist. Excessively prolonged drying
results in the loss of seed vitality.
Cherry (Prunus spp.) The seeds of all common species of cherries have a
period of dormancy. Various species and varieties of cherry differ
somewhat in their stratification requirements. Some complete
after-ripening in a course of four weeks while others require as long as
14 or more weeks under the same conditions. The after-ripening seeds
germinate, and the seedlings grow freely at a temperature close to
freezing. Therefore, a long period of stratification cannot be recommended.
The following schedule is probably the safest:
Species         Period (days)           Temperature
P. mahaleb      88                      37
P. avium (Mazzard)100-125               37
P. serotina (Black)30-60                        30

While in stratification, cherry seed must be under fre-quent
observation, particularly during the last part of the recommended
stratification period. If the completion of after-ripening occurs too
far in advance of the time of planting (as evidenced by cracking of the
seed coat), the temperature of stratification should be lowered to 31oF
to 32oF for the rest of the stratification period.
Plum (Prunus spp.) Plum seed requires stratification.  The exact period
for plums varies with the species as well as with individual lots. The
common wild plum of Oklahoma (Prunus angustifolia) is usually well
after-ripened after stratification of 60 to 90 days at 34F to 40F. Plum
seed germinates freely at a low temperature once the after-ripening is
completed. Therefore, make periodic observations of stratified seed and
lower the temperature if germination starts too soon.
Peach (Prunus persica) & Apricot (Prunus armeniaca) At the time of
ripening, as much as fifty percent of the seed may be dormant. In
commercial nursery practice, peach stones are commonly planted in the
fall of the year. They usually germinate freely the following spring
because fall planting provides the proper conditioning. However, one can
expect somewhat better results if the seeds are stratified over winter
under controlled conditions and planted in the spring.  The most
favorable stratification temperature for the peach is between 32F an
45F. At this temperature, the seed after-ripens in approximately 75 to
100 days.  Persimmon (Diospyros virginiana) Propagation of persimmon is
considered difficult and germination of its seed uncertain. The seed is
dormant when ripe. The cause of the dormancy lying in the embryo.
Stratification at a low tempera-ture for a period of 20 to 40 days or
fall planting of unstratified seed has been reported effective in
breaking dormancy and forcing germination.

--
BevanRon of EarthNSky Farm   NW Georgia USDA Zone 7
34.498N 85.076W    Bev is Earth, Ron is Sky