Human interdependence with cultivated crops

Human interdependence with cultivated crops is both an ancient partnership and a fragile inheritance: people have shaped wheat and maize to thrive under cultivation, yet those changes have left the crops dependent on human care. In the post-disaster world, the loss of farming threatens the plants as well as the people, while a small box of corn seeds offers Ish and Joey a chance to renew that relationship.

A Reciprocal History

The account describes wheat and corn as traveling alongside people, like dogs and horses, as helpers on a long shared journey. Its description resists a simple story in which people alone domesticated plants. Wild grass first benefited from the disturbed, enriched soil around human campsites; in that sense, it adopted people before people adopted it. As people tended the grass, it grew taller and stronger and yielded more seed. The exchange brought greater abundance, but it also changed what the plants could live without.

That history makes cultivation more than a technique for obtaining food. It is a relationship sustained by human labor and by plants whose forms and habits have been altered through that labor. The crops reward care, but their dependence is part of the bargain: their success cannot be separated from the fields, seedbeds, and farming knowledge that people provide.

What Cultivation Changed

Wheat became better suited to tilled soil and seedbeds kept clear of competing grasses. When plowing ceased, volunteer wheat sprang up across thousands of acres in the first year, but its presence did not last. Native grasses returned, formed tough sod, and continued growing from the same roots; with each year of neglect, there was less wheat. Eventually, the account says, wheat remained only in scattered places in the dry lands of Asia and Africa, where it continued to grow as it had before agriculture.

Maize proved more vulnerable still. The plant had traveled far from the tropics of America with people, but its domesticated seed was held fast within a tough husk, so it could not shed its own seeds. The narrative describes it as having traded freedom for a fat, pampered life: it had become suited to human care at the cost of reproducing independently. It disappeared even sooner than wheat. On the Mexican Highlands, wild teosinte—the plant identified with maize’s wilder counterpart—still grew in thick clumps, but that persistence was not the same as the survival of cultivated corn.

These contrasting fates sharpen the central claim. Cultivation had not simply made crops more productive; it had made their continuation conditional. When human farming vanished, abandoned fields could briefly preserve some of its results, but they could not replace the ongoing relationship that had sustained the domesticated plants.

Seeds Returned, but Farming Did Not

The danger becomes immediate when Ish opens a small cardboard box brought back by the boys from a community near the Rio Grande. The kernels are not the large, flat yellow or white ones he expected. They are small, pointed, and red and black: a more primitive kind of corn, of the sort the Pueblo Indians had traditionally raised. Their appearance identifies them as different from the highly developed, perhaps artificially hybridized varieties Ish had imagined. The box carries living planting material from the expedition eastwards, and with it a possibility the community had nearly lost.

Ish explains to Joey that The Tribe had delayed trying to raise corn for so long that he could no longer find any living seed. Now there is another chance. He lets the kernels run through his fingers, and the thought of their future brings him peace. He and Joey take only two dozen kernels to parch over a gasoline-stove burner, a small use that Ish worries may be wasteful. Yet the moment also becomes instruction: he explains the corn to Joey, and hopes that the idea planted in the boy’s mind will matter more than the kernels used up. Seed survival depends on having something to plant; continuity also depends on passing on an understanding of why the seed matters.

The Limits of Recovery

The returned seed does not make the community farmers. The season is already too far advanced: cold weather would arrive before corn had grown much beyond its first sprouting, so planting must wait until the following year. Ish and Joey scout nearby for a suitable patch and discuss exposure, soil, and ways to keep wild cattle out. Their conversations show learning in progress, but they also reveal the gap between theoretical knowledge and practical skill.

The local conditions are poor for the task. Corn adapted to the hot, dry Rio Grande valley might not mature during the chilly, fog-covered summers near San Francisco Bay. Ish knows something of soils from studying geography, including how podzols and chernozems form, but recognizes that such knowledge does not make him a farmer. He has no green thumb, and nobody else in The Tribe has farming experience, although Maurine grew up on a farm. The absence of someone closely connected to the soil has already influenced the community’s outlook.

The episode therefore holds promise and difficulty together. Human beings may be unable to prosper without wheat and corn, the narrative concludes, but these crops are even less able to prosper without human beings. The box of kernels makes that dependence tangible: it contains the possibility of a new crop, not a guarantee. Cultivation must be restored through the conjunction of viable seed, suitable conditions, skill, and knowledge passed between generations.