Shenandoah herald. [volume] (Woodstock, Va.) 1865-1974, 1892-05-27
LABOR OF LICHENS.
THE WORK OF CURIOUS VEGE-
TABLE TOtLERS.
Their Duty Is to Prepare Soil for Fu-
ture Plants to Grow ln-rhey
Are Useful to Man
Plant Vitality.
// n MONG the most curious Of
"A the tribes of plants that
III grow in the world are the


a Washington Star writer. "They are
the first forms of vegetation which clothe
the bare rocks of newly made corol OF
volcanic islands in the midst of the
ocean. Their duty in the economy of
nature is to prepare q soil for future
plants to grow in. The manner in which
they accomplish this is most remarkable.
While living they manufacture cousid-
erable quantities of oxalic acid out of
the carbon and oxygen from the at
mosphere, and this acts chemically upon
the rock, especially if it is limestone,
eating it away and forming hollows
which retain the decayed vegetable par
ticles after the lichena themselves have
died.
"Thus the lichens may be said to dig
graves for the reception OF their own re-
mains, which are thus retained and made
to form the beginning Of soil. Sue
cessive generations Of these vegetable
toilers grow and contribute their sub
stance to the accumulations in the hol-
lows until plants of higher kind, seeds
of which are always aacat in the air, can
find root. So the moses and ferns fol-
low, and at length, through the progress
of growth and decay, sufficient thick
ness of soil is produced for tho nourish-
ment OF luxurlant hcrbage. Different
tribes of plants, of gradually increasing
size and strength, follow one another
until, in the course of years, the sterile
rock is converted into a garden, of
which the productions, rising from
grasses to shrubs and trees, present all
the varieties of the fertile meadow, the
tangled thicket and the spreading forests
of lofty trees.
"Besides this important office in the
making of world, some of the lichens
are especially useful to man on account
of the valuable dyes they afford. The
blue dye called 'litmus, which Is changed
to a bright red by the action of acids, is
obtained from several species Of lichen
growing in the CauaIy Islands and else
where. Upon lichens the people of Lap
land depend for their subsistence, mas
much as q species called reindeer moss
supplies their reindeer with food through
the winter, its growth not being checked
by the snow beneath which it develops.
A sort of Arctic lichen has saved many
adventurous explorers from starvation.
In the realms Of perpetual frost the snow
which never melts on mountains or in
valleys is sometimes Redeemed for miles
by minute vegetable, formerly imagined
to have fallen from the sky and called
red snow 1t also is lichen.
"It would seem as il scarcely any
locality was too hot or too cod for
plants to grow in. Certain vegetable
growths flourish in a hot spring On the
Manila Islands, the temperature of
which is 1877 degrees Fahrenheit. Shrubs
and trees grow in hot springs of Louisi-
ana, the waters of which raises the ther-
mometer to 145 degrees. Vegetation of
certain kinds has been observed in boil
ing geysers of Iceland, which will cook
an egg in four minutes. Bulbs have
been known to fructify in sand that was
at heat far exceeding that Of boiling
water. Instances are recorded of bulbs
unrolled from the bandages of Egyptian
mummies which sprouted and grew upon
being planted, but it ia probable that
such cases were cheats BY the natives on
credulous travellers.
Nevertheless, it cannot be said that
such thing is altogether impossible.
The seeds Of most plants are endowed
with a remarkable power of preserving
their vitality for an unlimited time un-
der conditions not calculated to cause
sprouting nor to occasion decay. Given
a moderate temperature, drYness and alb
sence OF oxygen there is apparently
hardly any limit to the period during
which seeds may preserve within them.
selves the elements of life. Several
kinds kept in the berbarirm Of famous
French botanist were found to have re.
tanned their fertility after the lapse of
nearly a century. Very often virgin
ggound that is turned up newly spon-
taneously produces plants different from
any in their neighborhood, which are
derived from seeds taat have lain for a
long period embedded in the soil at such
a distance from the surface as to prevent
the access OF air AMI moisture.
"some years ago in Maine laborers
sinking a we'll about forty miles from
the sea struck layer Of sand at depth
Of forty feet. This excited curiosity,
because no sand like It was to be found
anywhere nearer than the ocean beach.
The sand was scattered about on the
surface Of the ground, aud from the area
covered by it a great number of small
trees quickly sprang. They were finally
asccrtained to be beach plum trees, and
they actually bore beach plums, which
had never before been seen except upon
the very seashore. It Is believed that
they must have grown from seeds which
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