The Inca in Peru -- Experts in Innovation

December 5th-8th, 2012; Around Cuzco, Peru --

What do you do when you run out of land on which to raise the crops that you and your civilization need to eat? The Inca give us a glimpse of what they did to solve their dilemma in this respect: they constructed level land -- and developed the irritation* systems to make it productive. But exactly how they did some of the things they did -- it is still a subject of mystery and conjecture.

• * The word, "irritation" was intended to read, "irrigation"; however, this typo is fruitious in that the construction of these agricultural developments provided considerable irritation to explorers, like Grumpy, who clambered up and down these sites centuries later.

John Deere tractor plowing a field.

Span of oxen plowing in adjacent field

Here are a couple photos of some quite level and rich soil, albeit at the elevation of 12,000 feet above sea level. Grumpy was told that the Inca occupied (lived on and cultivated) this area. Grumpy was fascinated by this contrast of the John Deere tractor and the span of oxen working in adjacent fields.

The city of Cuzco, situated on the bottom of a prehistoric lake, was also home to a large population of Inca at the time the Spaniards arrived. So why did the Inca find it necessary to construct crop lands in such inhospitable places as Moray, or Pisac, or Ollantaytambo --- or Machu Picchu!? Probably for the same reason the present world is running out of areas where crops can be productive -- partly because of the encroachment of pavement and warehouses onto our most tillable land. The effort to which the Inca went to develop crop lands should be a lesson for us to be better stewards of this precious commodity of which we still have quite a bit.

One of the most unique Inca sites is called Moray; it was built around a crater-like formation that may have been a "sink hole", since some of this area is limestone. There were actually two natural, circular depressions at this site plus an additional one that appeared to Grumpy to have been formed by damming an adjacent ravine. This site included a comprehensive irrigation system, utilizing water from surface run-off plus a diversion from a spring in another nearby valley. Most of this irrigation system was intact and functional.

The site that had the most elaborate irrigation system, and the one that was actually functioning when we visited, was at Tipon. Here on the left is a view across the series of nearly-level fields; the fields slope gently down toward their lower retaining wall. On the right is the irrigation canal bringing water along this side wall to various spots where it is diverted into cross-field canals (located next to the wall separating it from the field above it), from which each individual field can be flood-irrigated. This is the most water-efficient method of irrigation; least water is lost to evaporation, as is the case with "sprinkler" irrigation.

The Inca site that most clearly demonstrated the apparent desperation of the Inca to be able to grow crops in order to survive, was at Machu Picchu. Here in this part of Peru is the most "vertical" topography Grumpy has ever seen! Yet a hardy group of Inca came to this location (following a ridge from higher ground closer to Cuzco) to establish this settlement; then, after "only" 15 years, they inexplicably left, taking all of their belongings with them. To have accomplished as much as they did in only that short time is amazing in itself. The fact that they "made" fields on hillsides as steep as the one you see in the photo on the right is absolutely stunning to Grumpy. As you may note, the lower fields virtually stop only because below it is a near-vertical cliff.