Silent Spring

by Rachel Carson

Albert Schweitzer who said “Man has lost the capacity to foresee and to forestall. He will end by destroying the earth.”

I am pessimistic about the human race because it is too ingenious for its own good. Our approach to nature is to beat it into submission. We would stand a better chance of survival if we accommodated ourselves to this planet and viewed it appreciatively instead of skeptically and dictatorially. E. B. W

The chemical industry, one of the chief beneficiaries of postwar technology, was also one of the chief authors of the nation’s prosperity. DDT enabled the conquest of insect pests in agriculture and of ancient insect-borne disease just as surely as the atomic bomb destroyed America’s military enemies and dramatically altered the balance of power between humans and nature. The public endowed chemists, at work in their starched white coats in remote laboratories, with almost divine wisdom. The results of their labors were gilded with the presumption of beneficence. In postwar America, science was god, and science was male.

“Intoxicated with a sense of his own power,” she wrote, “[mankind] seems to be going farther and farther into more experiments for the destruction of himself and his world.” Technology, she feared, was moving on a faster trajectory than mankind’s sense of moral responsibility.

Carson believed that these chemicals were potentially harmful to the long-term health of the whole biota. The pollution of the environment by the profligate use of toxic chemicals was the ultimate act of human hubris, a product of ignorance and greed that she felt compelled to bear witness against. She insisted that what science conceived and technology made possible must first be judged for its safety and benefit to the “whole stream of life.”

the postwar culture of science that arrogantly claimed dominion over nature was the philosophic root of the problem.

All forms of life are more alike than different.

Global contamination is a fact of modern life.

As Albert Schweitzer has said, “Man can hardly even recognize the devils of his own creation.”

Given time—time not in years but in millennia—life adjusts, and a balance has been reached. For time is the essential ingredient; but in the modern world there is no time.

Thus the chemical war is never won, and all life is caught in its violent crossfire. Along with the possibility of the extinction of mankind by nuclear war, the central problem of our age has therefore become the contamination of man’s total environment with such substances of incredible potential for harm—substances that accumulate in the tissues of plants and animals and even penetrate the germ cells to shatter or alter the very material of heredity upon which the shape of the future depends.

Yet is our real problem not one of overproduction?

the picture began to take form—the poison being picked up by the smallest organisms, concentrated and passed on to the larger predators.

It was a house-that-Jack-built sequence, in which the large carnivores had eaten the smaller carnivores, that had eaten the herbivores, that had eaten the plankton, that had absorbed the poison from the water.

we are reminded that in nature nothing exists alone.

In other experiments BHC, aldrin, lindane, heptachlor, and DDD all prevented nitrogen-fixing bacteria from forming the necessary root nodules on leguminous plants. A curious but beneficial relation between fungi and the roots of higher plants is seriously disrupted. Sometimes the problem is one of upsetting that delicate balance of populations by which nature accomplishes far-reaching aims. Explosive increases in some kinds of soil organisms have occurred when others have been reduced by insecticides, disturbing the relation of predator to prey. Such changes could easily alter the metabolic activity of the soil and affect its productivity. They could also mean that potentially harmful organisms, formerly held in check, could escape from their natural controls and rise to pest status.

The earth’s vegetation is part of a web of life in which there are intimate and essential relations between plants and the earth, between plants and other plants, between plants and animals. Sometimes we have no choice but to disturb these relationships, but we should do so thoughtfully, with full awareness that what we do may have consequences remote in time and place.

It was no accident, but rather the result of long ages of experimentation by nature, that the great plains of the West became the land of the sage. Along with the plants, animal life, too, was evolving in harmony with the searching requirements of the land.

Most such animals have a digestive system of extraordinary complexity, including a stomach divided into four chambers. The digestion of cellulose is accomplished through the action of microorganisms (rumen bacteria) in one of the chambers. When the animal feeds on vegetation containing an abnormally high level of nitrates, the microorganisms in the rumen act on the nitrates to change them into highly toxic nitrites. Thereafter a fatal chain of events ensues: the nitrites act on the blood pigment to form a chocolate-brown substance in which the oxygen is so firmly held that it cannot take part in respiration, hence oxygen is not transferred from the lungs to the tissues. Death occurs within a few hours from anoxia, or lack of oxygen. The various reports of livestock losses after grazing on certain weeds treated with 2,4-D therefore have a logical explanation. The same danger exists for wild animals belonging to the group of ruminants, such as deer, antelope, sheep, and goats.

“Once again we are walking in nature like an elephant in the china cabinet.” So C. J. Briejèr, a Dutch scientist of rare understanding, sums up our use of weed killers. “In my opinion too much is taken for granted. We do not know whether all weeds in crops are harmful or whether some of them are useful,” says Dr. Briejèr.

What is the relation between the weed and the soil? Perhaps, even from our narrow standpoint of direct self-interest, the relation is a useful one. As we have seen, soil and the living things in and upon it exist in a relation of interdependence and mutual benefit. Presumably the weed is taking something from the soil; perhaps it is also contributing something to it.

Marigolds are now used in many places for combating nematodes.

In the same way, and perhaps quite unknown to us, other plants that we ruthlessly eradicate may be performing a function that is necessary to the health of the soil. One very useful function of natural plant communities—now pretty generally stigmatized as “weeds”—is to serve as an indicator of the condition of the soil.

The success of selective spraying for roadside and right-of-way vegetation, where it has been practiced, offers hope that equally sound ecological methods may be developed for other vegetation programs for farms, forests, and ranges—methods aimed not at destroying a particular species but at managing vegetation as a living community.

extremely effective control of many kinds of unwanted vegetation might be achieved by paying more attention to the role of plant-eating insects. The science of range management has largely ignored this possibility, although these insects are perhaps the most selective of all grazers and their highly restricted diets could easily be turned to man’s advantage.

The most effective and widely distributed is a parasitic wasp from Korea and China, Tiphia vernalis. The female Tiphia, finding a beetle grub in the soil, injects a paralyzing fluid and attaches a single egg to the undersurface of the grub. The young wasp, hatching as a larva, feeds on the paralyzed grub and destroys it. In some 25 years, colonies of Tiphia were introduced into 14 eastern states in a cooperative program of state and federal agencies. The wasp became widely established in this area and is generally credited by entomologists with an important role in bringing the beetle under control.

An even more important role has been played by a bacterial disease that affects beetles of the family to which the Japanese beetle belongs—the scarabaeids. It is a highly specific organism, attacking no other type of insects, harmless to earthworms, warm-blooded animals, and plants. The spores of the disease occur in soil. When ingested by a foraging beetle grub they multiply prodigiously in its blood, causing it to turn an abnormally white color, hence the popular name, “milky disease.”

No method had been developed for growing the disease organism in an artificial medium, but a satisfactory substitute was evolved; infected grubs are ground up, dried, and combined with chalk. In the standard mixture a gram of dust contains 100 million spores.

Substitute for milky disease in beetles; milky spore disease

Those who want immediate results, at whatever cost, will doubtless continue to use chemicals against the beetle. So will those who favor the modern trend to built-in obsolescence, for chemical control is self-perpetuating, needing frequent and costly repetition. On the other hand, those who are willing to wait an extra season or two for full results will turn to milky disease; they will be rewarded with lasting control that becomes more, rather than less effective with the passage of time.

The question is whether any civilization can wage relentless war on life without destroying itself, and without losing the right to be called civilized.

By acquiescing in an act that can cause such suffering to a living creature, who among us is not diminished as a human being?

The so-called Dutch elm disease entered the United States from Europe about 1930 in elm burl logs imported for the veneer industry. It is a fungus disease; the organism invades the water-conducting vessels of the tree, spreads by spores carried in the flow of sap, and by its poisonous secretions as well as by mechanical clogging causes the branches to wilt and the tree to die. The disease is spread from diseased to healthy trees by elm bark beetles. The galleries which the insects have tunneled out under the bark of dead trees become contaminated with spores of the invading fungus, and the spores adhere to the insect body and are carried wherever the beetle flies. Efforts to control the fungus disease of the elms have been directed largely toward control of the carrier insect.

“I am dreading the days to come soon now when many beautiful birds will be dying in our back yard,” wrote a Milwaukee woman. “This is a pitiful, heartbreaking experience . . . It is, moreover, frustrating and exasperating, for it evidently does not serve the purpose this slaughter was intended to serve . . . Taking a long look, can you save trees without also saving birds? Do they not, in the economy of nature, save each other? Isn’t it possible to help the balance of nature without destroying it?”

Other possibilities lie within the field of forest genetics, where experiments offer hope of developing a hybrid elm resistant to Dutch elm disease. The European elm is highly resistant, and many of them have been planted in Washington, D.C. Even during a period when a high percentage of the city’s elms were affected, no cases of Dutch elm disease were found among these trees.