
The Chinese city of Yulin is on the edge of the Maowusu desert, which occupies the southernmost part of Inner Mongolia. Just north of the city was Mongol territory, and so heavily eroded remnants of the Great Wall cut through the suburbs ? or, rather, cut through what would be the suburbs if Yulin were a town in the U.S., but in China is an armada of coal-powered factories. Zhenbeitai, one of the Great Wall's three most important forts, is in Yulin.
I was in Yulin to research my book, 1493, but naturally I wanted to see this part of the Great Wall. Josh D'Aluisio-Guerrieri, my friend and translator, China-hand supreme, was willing to go along. In China, foreigners can't rent cars, so Josh had arranged for a taxi. The idea was that we would stop at the Wall when we finished work for the day.
Driving northwest from Yulin, the highway was boxed in by endless lines of replanted trees ? part of China's huge effort to reforest this area. We couldn't see actual desert until we left the main route and drove on little country roads. We had no particular destination in mind. We just took roads into villages until the asphalt petered out then walked around and talked to people. Do this enough, and you start to get a hint of what a place is like.
What it was like: a desert. Here and there were low thorn bushes. Trees scraggly in yards and along the roads. Otherwise the land was almost pure sand ? we could have mined for sandboxes.
Incredibly, the villagers were harvesting corn (maize, if you're outside the U.S.). It was as if they were farming a beach.
China has a fifth of the world's people but less than a 10th of its fresh water. Most of that water is in two big rivers, the Yangzi and the Huang He (Yellow). How unfortunate that the nation's main crop is rice, grown in irrigated paddies! For farmers, China's vast, dry uplands were almost completely useless. Even though the Huang He was coursing through the canyons just 60 miles east, this land had never felt the plow or axe.
Columbus changed all that. Portugal brought American maize to its colony in Macao in the 16th century. Spaniards brought American sweet potatoes to Spain's outpost in Manila. Both will grow just about anywhere. China surged out of river valleys and into the uplands. As the University of Chicago historian Ho Ping-ti (He Bing-di, in China) has noted, sweet potato, not rice, was "the poor man's staple" in northern China by 1800. Corn played the same role in the west and southwest.

For a long time the results were spectacularly good, Ho said. Chinese farmers' yields soared; China's population boomed. But as time went by, Ho argued, it became apparent that farmers who had never planted crops in this kind of soil before were making beginners' mistakes. They planted in areas so steep and so dry as to be wildly unsuitable even for corn and sweet potatoes. The resultant erosion caused massive floods ? floods that make our own problems on the Mississippi look small and uncommon. The loss of life, public anger, vast expense, and destabilized food supplies caused by the floods helped topple the Ming dynasty.
Destroy Forests, Open Wastelands!
I was fascinated by this story, but wondered if it was actually true. Could things have been as bad as that? I didn't want to put these ideas in my book if they didn't pass the silly-grin test. Part of the reason I went to Yulin was to find out whether it was possible to make such a mess.
Incredibly, Mao had repeated the same mistakes. Proclaiming revolutionary war-on-nature slogans ? "Move Hills, Fill Gullies and Create Plains!" "Destroy Forests, Open Wastelands!" ? villagers fanned out across the hills in the 1960s and 1970s, cutting down vegetation, terracing slopes, and planting on every flat surface. Still more massive erosion was the result, along with the usual flooding, dislocation, and massive public expenditure. Massive dust clouds blew east as far as Beijing. Remember those replanted trees? That was the government trying to undo its own past actions. Meanwhile, farmers kept planting ? what else could they do?
In the afternoon, we stopped at the Great Wall. In that area, at least, the Wall had little towers every quarter of a mile or so, so that soldiers could communicate by waving flags. The towers were close enough so that visibility was good.
A combination of coal smoke and airborne sand had changed things. When we arrived, we could barely see from one tower to another. The picture below was taken an hour before sunset on a day without a cloud in the sky.
Trucks thundered by on the highway as we clambered along the eroded wall. Dust was all over my clothes and in my nose. I was beginning to believe that it really might be possible to make such a mess.
A Really Good Book
These blog posts are supposed to sound like chatty updates from this interesting fellow you'd want maybe to know while actually being advertisements for a commercial product (my book). Creepy, right? To neutralize the whiff of bad faith, at least a little, I thought I could talk about other writers' books ? books that I could tout with a clear conscience, because I get no benefit from it. At the end of each post in my little stint I'm extolling a book that was both helpful to 1493 (thanks!) and might be fun to read for somebody who is not researching the subject.
Because part of 1493 is about how the Spanish empire was a Real Big Deal, I read a lot of histories of said empire. The most enjoyable, at least to me, was Henry Kamen's smart, concise, sophisticated Empire. One of many passages I underlined, chilling to read nowadays, is about how the Spanish government increasingly outsourced its functions to the private sector and ended up ceding operational control to foreign entities:
Like any great enterprise, [the Spanish empire] was highly expensive to run. In times of peace, basic operations such as communications, trade and transport of supplies between the territories of the monarchy required a degree of efficiency that the central government could never guarantee, since it had no personnel who could carry out the task. Virtually all the important operations were therefore contracted out. Even the collection of the crown's own taxes was contracted, since there were no internal revenue officials. As in any large business, it was the ability to arrange transactions and move money that ensured success. To achieve this, the crown resorted to international bankers....All [of the empire's] nerve centers slipped firmly into the hands of outside businessmen who did not intend to let pass the opportunity to control the source of their profits. Without exception, Castilian traders and financiers were relegated to a secondary role.