The British Agricultural Revolution and The Industrial Revolution.

http://en.wikipedia.org/wiki/British_Agricultural_Revolution
http://en.wikipedia.org/wiki/Industrial_Revolution

Where are we going to expand to next?

"that what we have here is cognitive dissonance rather than technological (or, in this case, agricultural) incapacity."

Ultimately, a bottleneck is a bottleneck. Saying it is one not the other seems to imply that unplugging the blockage is therefore no big deal.

As with the arguments we hear saying 'There's plenty of Sun and Wind, so there's no energy crisis to worry about..' These transformations take time, training and often new tools and attitudes.. and as they said, there's real doubt that we have enough time to do these things as an Eleventh-hour patch-job. Those Hedge-gardens with nut trees and carefully designed combinations and accumulations of plant and animal species also do not arrive overnight.

.. I would say that this film was extremely serious about some well-reasoned cautions, but never really got to 'Near Hysteria'.

Thanks for the enlightening info Dayahka. I remember when my English grandfather was alive. He worked in the garden providing not only his family, but ours as well, until the day he finally didn't get out of bed to fetch the eggs from the hen house. As for:

"We did it before, why can't we do it again? Is the problem less technological than psychological? It appears that people resist change and may be reluctant, unless forced, to do what people did in the past, pre-technological era, unless forced into it, so it may be that what we have here is cognitive dissonance rather than technological (or, in this case, agricultural) incapacity".

I recommend Nate's recent post:

"I Don't Know"

http://campfire.theoildrum.com/node/5221#more

Is the problem less technological than psychological?

Technically, yes. If you accept the contention that an acre can feed ten, then definitely, but it's an over-simplification to say we can technically do it.

Can the US? Yes. There are 1.3 acres of arable land per person. At 10 people per acre, we can feed ourselves and another twelve people. That's 3.7 billion people. At the historically stated rate of 1 person per acre, the US can still feed another 100M besides ourselves.

South Korea, on the other hand, couldn't feed themselves even at 10 people fed per acre because there is a shortage of arable land due to the country being very mountainous and the pop. density being nearly 400/sq. km. This is why a Korean conglomerate wanted to buy half of Madagascar.

Obviously, some trading will need to occur to keep the current population level fed.

Another consideration is time. Do we have time to transition to permaculture? Probably not. It would involve a massive movement of people back to the land either as laborers for Big Ag or as land owners. Let's say I work three acres for my three person family. Let's assume I can grow enough for ten per acre. That still means one in ten must farm to avoid mechanized agriculture. That's 10,000,000 Americans back on the land.

This link says there were just over 2M farms (A farm is any establishment from which $1,000 or more of agricultural products were sold or would normally be sold during the year) each averaging 449 acres in size in 2007. Many of those must be corporate. Those privately held are almost certainly run by one farmer for the most part. Figure with the spouse included and the occasional offspring sticking around, we're still way under 10M.

Regardless, running over 400 acres by hand is gong to be impossible no matter how little work it takes, so those farms need lots of farm hands or to be sold off as small holdings.

It would be great to see farmers break up their holdings, get a little nest egg out of it, retrain themselves in the P/NK methodologies and then act as mentors to the new farmers they've sold to.

My inexpert 2c.

Cheers

"What changes in agriculture occurred between 1700 and 1900?"
This happened.

http://en.wikipedia.org/wiki/Plough

The basic plough with coulter, ploughshare and mouldboard remained in use for a millennium. Major changes in design did not become common until the Age of Enlightenment, when there was rapid progress in design. Chinese ploughs, with mouldboard, were brought to Holland in the seventeenth century by Dutch sailors. And because Dutchmen were hired by the English to drain the East Anglian fens and Somerset moors at that time, they brought with them their Chinese ploughs. The English called these Chinese ploughs the 'bastard Dutch ploughs' instead of 'Chinese ploughs'. Thus, the Dutch and the English were the first to enjoy the efficient Chinese ploughs for the first time in Europe. The Chinese-style ploughs were spread to Scotland from England, and from Holland to America and France.[12][7]

https://statistics.defra.gov.uk/esg/reports/foodsecurity/foodsecurity.pdf

This government paper gives a good idea of how and when the UK became less self sufficient in food. By 1870 40% of food was imported. At present the figure is between 40 - 50% imports, with a population of around 65 million, using intensive oil-based agriculture. I have heard the suggestion of 20 million or lower as being sustainable. Depends how much we eat, and what.