balance of nature

The balance of nature is a changing system of relationships among organisms and their surroundings, not a static condition that human beings can disregard or redesign without consequence. The book uses the concept to challenge chemical campaigns and land management that treat a target species or plant as a problem in isolation: nature’s restraints are interconnected, and weakening them can produce consequences that the intervention was meant to prevent.

A Dynamic System of Relationships

The account rejects the notion that ecological balance belongs only to an earlier, simpler world. The balance is not identical to the conditions of the Pleistocene, and it does not mean that nature remains unchanged. It is fluid, continually adjusting, and composed of precise, integrated relationships among living things. Human beings are part of this system, not observers standing outside it; its shifts may favor people or, through human activity, work against them.

That distinction gives the expression its practical force. To call nature balanced is not to claim that every population is fixed or that every change is harmful. It is to recognize that species, food, climate, and predation interact, so an action aimed at one element may alter conditions elsewhere. A management program that measures success only by the removal of its chosen target can therefore overlook the relationships that made the target’s abundance—or its restraint—possible.

The Sage Country as a Natural System

The western sage country makes those connections visible in a particular landscape. The high plains and lower mountain slopes formed through the uplift of the Rocky Mountain system millions of years ago and developed under harsh climatic extremes. Over long periods, plants and animals adapted to those conditions. The pronghorn and sage grouse, like the sage itself, belong to an ecological arrangement shaped by the demands of the land.

That arrangement comes under pressure when agencies seek more grazing land by replacing sagebrush with grass. The policy treats sage as an obstacle to cattle production, but the land is not simply grass waiting to be released from an unwanted plant. Sagebrush and bitterbrush provide wild vegetation that sheep may need during winter storms; the attempt to improve the range for one use can diminish the resources on which animals depend in another. The landscape’s meaning lies in these relations, not in a single measure of productivity.

The consequences extend beyond the intended vegetation. In the account of the Bridger National Forest, the United States Forest Service sprayed about 10,000 acres of sage country under pressure from cattlemen. Willows were also killed by the indiscriminate spray. They had supported beavers, and the region had offered recreation, fishing, and hunting; when the Forest Service’s intervention reached beyond sagebrush, it altered habitat and the uses people had made of it. The example shows how a landscape treated as a target area can carry a wider ecological and public cost.

Environmental Resistance and Population Surges

The book identifies environmental resistance as nature’s effective control of insect populations. Available food, weather and climate, and competing or predatory species all help limit abundance. Insects also restrain one another: entomologist Robert Metcalf described their internecine conflict as a major factor preventing them from overwhelming other life. Broad-spectrum chemicals, however, kill beneficial and harmful insects alike, weakening the very relationships that can hold populations in check.

A second neglected consideration is the reproductive capacity released when those restraints are weakened. The book warns that many forms of life can reproduce on a scale difficult to imagine. In this framework, a pesticide’s immediate success against its target does not establish lasting control. If it removes predators or competitors, it may leave the conditions for the surviving or later-growing population more favorable than before. The intervention can thus create a reversal: the apparent victory over a pest becomes a risk of renewed abundance.

The coyote and the Kaibab deer provide parallel examples of this failure to account for relationships. Efforts to eliminate coyotes have led to field-mouse plagues, because the predator had helped control them. In the Kaibab example in Arizona, the deer population increased after predation was reduced, then exceeded what the environment could sustain. Many more deer died of starvation than had formerly been killed by predators, and their desperate search for food damaged the surrounding environment. The sequence makes the book’s point concrete: removing a constraint is not the same as solving a problem, and an increase in one species can bring suffering and environmental damage in its wake.

Predatory insects occupy a comparable position in fields and forests. Like wolves and coyotes, they limit prey populations; killing them can allow those populations to surge. The comparison connects familiar wildlife-management failures to insect control and warns against treating predatory species as expendable simply because they are not the intended target. The same ecological reasoning applies across scales: the relevant unit is not an isolated organism but the network of conditions and relations in which it lives.

Why the Concept Matters

The balance of nature serves as a corrective to the assumption that a few tests on individual species are enough to justify action against living communities. Chemicals may be tested against selected organisms without being tested against the communities those organisms inhabit. The book presents that gap as consequential: a program can appear precise at the level of its chosen target while acting broadly on food sources, predators, competitors, plants, and habitat.

This is why the balance is neither a nostalgic ideal nor a promise that nature will remain benign. It is a warning about dependence and response. Human activity can shift ecological relations to human disadvantage, while surviving populations and altered environments may answer in ways a campaign did not anticipate. The final image of chemicals hurled against the fabric of life gathers the concept into a caution: that fabric is destructible, yet resilient enough to strike back in unexpected ways. Effective accommodation, the book argues, requires working with living systems rather than trying to force them into channels through indiscriminate poisoning.