Evening star., 1926-05-13
BACKGROUND OF EVENTS
BY PAUL y. COLLINS.

which they rubbed off upon the pistils
of the Smyrna blooms.
The scientist shipped TO California
some of the Capri trees, at the bios
soming season. bearing the eggs NJ
the wssps, and there, in California. the
wasp eggs Matched and the young
wasps did just as had their ancestors
done in Smyrna--carried Capri pollen
into the pistils of the Smyrna trees,
and behold new industry was Great
ed in California, which produced fgs
as delicious as those of Asia Minor.
Without the fruitless Capri trees
there could be no wasps; without the
wasps. outnumbering the blooms OF
Capri, there could be no matured
fruit upon the Smyrna trees of
America.
While we owe to the world our
many fruits and vegetables, the world
owes to America its corn, potatoes,
tomatoes and tobacco.
There is flare back" in which
both America and Europe are in
vOlved. We gave to Europe the white
pine. Later. some of our nurseries
imported from Germany white pine
seed; with ii they also brought in a
certain disease which had not been
important in Europe. That fungus
disease passes one of its stages as a
parasite upon gooseberries or cur
rants. and soon it became virulent in
America. 1t cannot he eradicated,
but II care is taken to keep goose
berries and currant bushes at least
500 to 900 feet from the white pine,
the blister rust does not reach II.
In that narrow neutral zone. the
blister rust is controlled. But il takes
a much wider neutral zone between
barberry and wheat to keep the black
rust out of the grain. which comes
from the disease germ harbored in
barberry. Airplane traps. high in the
sky, demonstrate that germs hy many
miles. in the upper strata.
The most serious introduction Of
plant disease Is the fungus. which is
destroying the chestnut forests. No
spray reaches the fungus This
fungus was found on Manhattan Is
md about 10 or IL years ago: today
it has spread from Maine TO South
Carolina. and within 20 years it will
infest all chestnut trees in the United
States: within 40 years there will he
no more of this most valuable tree.
Leather can be tanned with a
blend of oak. hemlock and a certain
tropical tannin. hut chestnut is
preferred for sole leather. Oak and
hemlock can he used for other
feathers. but it is not so favored for
sole leather as chestnut. Army au-
thorities are concerned over the loss
of chestnut tannin. and the substitute
of the blend requiring the tropical
tannin, because, in time of war. i'm
ports would be imperiled upon the
seas.
1t Is found that while the fungus
comes from China. whence the
original chestnut came. it is not
troublesome in China. and scientists
are now seeking in China specimens
of fungus-resisting chestnuts for i'm
portation and development in the new
arboretIIm.
DIR. Taylor suggests that the sup
ply OF Army shoes may be seriously
affected by the success in this
arboretum of resistant chestnut trees
which. it Ia hoped. will supplsnt the
American chestnut.
~ *
What is needed for facilitating scien-
tific attacks on plant diseases is a
complete collection in the arboretum
of all the varieties-wild and cultivat
ed-Of all trees and shrubs. so that Z
the scientist can watch their action
under all conditions. Often the
bybrids produced by crossing two
widely separated parent plants are
harder and more desirable than
either parent.
AT the Arlington experiment station
DR. Waite is growing 1000 hybrid
pears. and Is greatly encouraged be-
cause, out of the 1900 specimens.
there are or 10 which he finds
promising"
In France Orchardists very often
train peach. apple and pear trees into
vines, cutting off all side branches and
fastening the vines against stone
or brick walls. They claim that they
thus. get finer fruit. But the practice
is not favored in America. as DIR.
Taylor explains. becau use OF the higher
la Dor costs. and. particularly. because
our sunshine is so much more bril-
liant than that of Sunny France"
that the fruit does not need the extra
benefit of the reHection of heat and
light from the walls.
In an address by Prof. John Merle
Coulter at the dedication of the
Brooklyn Botanic Garden laboratory.
he referred to the social and educa-
tional advantages OF such institutions,
and added:
THE general impression Is tnat
pure science holds no relation ia
public welfare. and that applied
science serves our needs. IL we had
only applied science it would soon he
come sterile. II is pure or fundamental
science that makes progress possible.
For example. II Faraday had not
worked in pure science. Edison would
have had no basis for his wonderful
lcopyrirhs. isee. ey. Paulsy cellip- :