Evening star., 1942-05-21
Of Stors, Men 3:
And Atoms
Notebook Of Science Progress
In Laboratory, Field
And Study
BIZ Thomas r. Henri.

BY Thomas r. Henry.
Guayule, Mexican desert shrub which
eventually may be a source Of consider
able natural rubber, Is proving . highly
temperamental plant
This is the experience Of United
States Forest Service oficials who ex-
pect to plant approximately $4,000 acres
through the Southwest with 1t by next
spring. They now have about 500 acres
in the Salinas valley Of California sown
with $4,000 pounds OF seed, which they
hope will yield enough seedlings for the
larger planting project.
Meanwhile, test plots are being es-
tablished through the Who'll. region from
California to East Texas in the hope of
finding places with just the right bal
ance Of rainfall and sunshine for the
newly domesticated plant. 1t will grow
almost anywhere, they have found,
providing the temperature does not fall
below five above zero in winter. Pref
erably 1t should not be below IS above.
But 1t will not make any appreciable
amount OF rubber unless there Is An
approximately equal wet and dry sea-
son, and the wet season must not be
very wet. Evidence is accumulating to
the effect that guayule stores rubber
under its bark-actual granules Of rub
Der, by the way, and not the milky
latex that comes from the rubber tree
only through a rainless season. But 1t
demands moisture for growth. Places
adapted to its culture are proving few,
although the Department of Agriculture
specialists are combing the Southwest
for such spots
The seedlings now being planted will
contain from IS to 10 per cent rubber.
dry weight, when they are four years
old. This will mean about 1900 pounds
to The acre Some plants developed by
the Intercontinental Rubber Co.. whose
nursery has been taken over by the
Government. yield As much s "a per
cent Of rubber, dry weight: and new
strains now are being developed which
may approach this figure.
AS with everything else connected
with the rubber situation, there has been
a lot Of misinformation about guayule.
For the next four years the actual rub
Der production will be very small.
Forest Service ofiicials say. Even when
the crop Is established, 1t will require
expert cultivation and lot OF back
breaking work
At one time 1t was proposed TO use
interned japanese gardeners on the
Pacific coast-many Of them perfectly
loyal to the United States-on this work,
but 1t has been found that one man
might do a lot OF damage. Guayule
and weeds come up together and the
weeds will kill out the rubber plant
unless they are constantly pulled by
hand until 1t has attained a respectable
growth.
All sorts OF folks through the South
west, and even in parts of the country
where the culture would be impossible,
are asking for seeds. They evidently
are under the misapprehension that all
one needs to do is to SOW it broadcast
over sandy area good for nothing
else. Then. they think, they can sit
back and reap the rewards four years
later. There even is reported to have
been some swindling In guayule planta-
ton stock. But, in any event, the Gov
eminent has no seeds to spare.
Up to the present, Forest Service
officials declare, the experiment looks
promising but they cannot predict with
any confidence that 1t will be a COM
plete success The Salinas Valley plan
tations Of the Intercontinental Rubber
Co. were successful, but 1t now appears
that they were in the one area Of the
world best adapted for the plant. Its
growth and yield cannot be predicted
with assurance anywhere else.
1t grows wild In the Mexican desert
under unpromising conditions. But .
wild plant is much like a wild animal
Few thrive in captivity except after q
long domestication process and some
never can be domesticated successfully.
The hevea rubber tree is a partial ex-
ample Of this. Until very recently it
was not possible to domesticate 1t In its
native land, Brazil, although 1t throve
in the East Indies.
New life expectancy. tables for the
American population, such as form the
general basis Of life insurance policies,
have Just been compiled by the Bureau
of the Census.
records for various areas of the coun-
try for the period 1930-1939 inclusive.
and constitute the most searching analy-
sis yet made of the probabilities Of length
of life in different regions.
While general life expectancies for the
country as a whole remain little changed
since the last tables were issued, re-
markable differences are shown from
one area to another for various age
groups.
For example, the tables show, people
live longer in the west North Central
States-Minnesota, the Dakotas Iowa.
Missouri, Nebraska and Kansas-than
in any other part of the country. The
average baby. at birth, has normal ex-
pectancy of 647 years. In the mountain
States, on the other hand, the average
length of life is only so years.
This is due in part, the Census Bu-
reau statisticians believe, to the fact
that so many tubercular patients settle
in the Rocky Mountain area. They prob
ably live longer there than they would
elsewhere, but their lives are so short
that they pull down the average.
Second come the Pacific Coast States