Silent Spring by Rachel Carson

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die out, with far-reaching cons equences to the ecology of the whole region. Many herbs ,
s hrubs , and trees of fores ts and range depe nd on native i ns ects for their reproduction; without
thes e plants many wild animals and range stock would find little food. Now clean cultivation
and the chemical des truction of hedgerows and weeds are eliminating the las t s anctuaries of
thes e pollinating ins ects and breaking the threads that bind life to life.
These insects, so essential to our agriculture and indeed to our landscape as we know it,
deserve something better from us than the s ens eless des truction of their habitat. Honeybees
and wild bees depend heavily on s uch ‘weeds ’ as goldenrod, mus tard, and dandelions for pollen
that s erves as the food of their y oung. Vetch furnis hes es s ential s pring forage for bees before
the alfalfa is in bloom, tiding them over this early season so that they are ready to pollinate the
alfalfa. In the fall they depend on goldenrod at a s eas on when no othe r food is available, to
s tock up for the winter. By the precis e and delicate timing that is nature’s own, the emergence
of one s pecies of wild bees takes place on the very day of the opening of the willow blos s oms.
There is no dearth of men who unders tand thes e things , but thes e are not the men who order
the wholesale drenching of the landscape with chemicals.
And where are the men who s uppos edly unders tand the value of proper habitat for the
preservation of wildlife? Too ma ny of them a re to be found defending herbicides as ‘harmless ’
to wildlife because they are thought to be less toxic than insecticides. Therefore, it is said, no
harm is done. But as the herbicides rain down on fores t and field, on mars h and rangeland, they
are bringing about marked changes and even permanent des truction of wildlife habitat. To
des troy the homes and the food of wildlife is perhaps wors e in the long run than direct killing.
The irony of this all-out chemical assault on roadsides and utility rights-of-way is twofold. It is
perpe tuating the problem it seeks to correct, for as experience has clearly shown, the blanket
application of herbicides does not pe rmanently control roads ide ‘brus h’ and the s praying has to
be repeate d year after year. A nd as a further i ron y, we pe rs is t in doing this des pite the fact that
a perfectly s ound me thod of s elective s praying is known, which can achieve long-te rm
vegetational control and eliminate repeated spraying in most types of vegetation. The object of
brus h control along roads and rights-of-way is not to s weep the land clear of everything but
grass; it is, rather, to eliminate plants ultimately tall enough to present an obstruction to
drivers ’ vis ion or inte rfere nce with wires on rights-of-way. This means, in general, trees. Most
s hrubs are low enough to pres ent no hazard; s o, certainly, are ferns and wildflowers.
Selective spraying was developed by Dr. Frank Egler during a period of years at the American
Mus eum of Natural His tory as director of a Committee f or B rus h Control Recommendations for
Rights-of-Way. It took advantage of the inherent s tability of nature, building on the fact that
mos t communities of s hrubs are s trongly res is tant to invas ion by trees. By comparis on,
grass lands are easily invaded by tree s eedlings. The object of selective spraying is not to
produce gras s on roads ides and rights-of-way but to eliminate the tall woody plants by direct
treatment and to preserve all other vegetation. One treatment may be sufficient, with a
possible follow-up for extre mely res is tant species; thereafter the s hrubs ass ert control and the
trees do not return. The bes t and cheapes t controls for vegetation are not chemicals but other
plants.
The method has been tes ted in res earch areas s cattered throughout the eas tern United States.
Results s how that once properly treated, an area becomes stabilized, requiring no respraying
for at least 20 years. The s praying can often be done by men on foot, us ing knaps ack s prayers ,

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