Viability of Seeds
Nature Bulletin No. 507-A November 17, 1973
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation
VIABILITY OF SEEDS
A viable seed is one capable of germinating and producing a new plant,
The question of how long seeds can remain dormant and retain their
viability -- still be able to sprout -- has interested botanists, naturalists,
foresters, and gardeners for many years but there is much more to be
learned about it. A great deal of misinformation has been given to the
public, such as fanciful yarns about wheat sprouting after its discovery
in ancient Egyptian tombs. The maximum viability of wheat is about 30
years -- usually far less.
Actually, many seeds are notoriously short-lived. Those of willows and
poplars must lodge in a favorable spot and germinate within a few days
after ripening, or they will not germinate at all. Nurserymen say also
that cottonwood, silver maple and American elm seeds should be
planted within two weeks after ripening, and their ability to germinate
decreases rapidly. Ash seed may be stored until the following spring.
White oak acorns must be planted as soon as gathered, whereas bur,
red, black, and pin oak acorns need not be planted until the following
spring if stored under proper conditions of temperature and moisture.
The Garden Dictionary lists corn, dandelion, onion, and parsnip seeds
as having an average viability of two years. Beet, carrot, lettuce, squash,
turnip, and watermelon seeds remain viable for an average of 5 or 6
years but under ideal conditions may exceed 10 years. Cucumber and
endive seeds are good for 10 years at least.
Our forest preserve plantsmen have found that hickory nuts and black
walnuts remain viable after two years or more in storage and should be
planted, as they are buried by squirrels, shallow. Their germination
depends not only upon the moisture and warm sunshine in spring but is
benefited also by freezing. That seems to be true of other plants. In our
nursery the seeds of the Kentucky coffee tree, linden, cherries, and
viburnums are "stratified" in autumn: layers of those seeds are placed
between alternate layers of sand in an open pit. Exposure to the rain,
snow and freezing during winter causes them to germinate more readily
when planted in spring.
Seeds with hard coats tend to be long-lived. That is noticeable among
the legumes -- which include the Kentucky coffee tree -- the mallows,
and especially, the lotus. In the Illinois River Valley there used to be
colonies of American lotus in swamplands now included in drainage
districts which have been levied, pumped dry, and cultivated for
decades. The farmers often uncover lotus seeds that are as hard and
viable as they were 50 years ago. Lotus seeds collected from ancient
lake beds in Manchuria have been established, by the Carbon 14
method, as being from 830 to 1250 years old. After thinning the shells
with a file, they were planted, some sprouted, and some produced
It has been demonstrated that, under ideal conditions of temperature, air
and humidity, other kinds of seeds may remain viable after lying
dormant for a long, long time. During the air raids of 1940, the Natural
History Museum in London was badly damaged. Due to heat from fire
and water used to put it out, a number of seeds -- stored there in
drawers -- germinated, including some from a silk tree which had been
collected in China in 1793.
In 1879, at Michigan State College, a lot of seeds were buried 20 inches
below ground in uncorked bottles. Fifty years later, they were taken up
and what kinds of seeds germinated .
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Update: June 2012