So, oil is dangerously close to the ‘psychological’ barrier of 100 dollars a barrel? I’m not sure I know what that means, but let’s just say that oil is getting pricey.

The fall out from this is that all manner of travel will get expensive and producing anything that depends on oil for energy will become more expensive. Most people only think it will be their summer holiday that is affected.

The one that is of real interest to me is food.

You see, food used to be really expensive to produce. A chicken, when I was young, was a luxury item that was reserved for Sunday (Ireland was pretty dirt poor in the 1970s, you have to remember and for sure, my family was not rolling in cash).

Go back about a hundred and fifty years and there were real problems with producing food. The Irish famine was the result of growing potatoes, because they were a high energy crop - lots of starch and lots of energy. The green revolution hadn’t occurred yet and the know-how wasn’t there to avert such dangers.

Then the green revolution occurred. The carbon, nitrogen and sulphur cycles were being understood, artifical fertilisers were introduced. New strains of wheat and potato were developed using husbandry techniques and control of variation by judicious selection of ‘good’ varieties. Food started to become more plentiful and diverse.

However, until the recent farm intensification, post 1930, the energy requirement for agriculture was lower. You grew spuds and they were fertilised by the manure produced by your cows and on a dry day you might have watered them using water from your stream. Because of strain improvements and intensification, at this time food became cheap to buy and it remains so today.

Now, water is much more scarce. We use it in all kinds of things from making CDs to hosing down roads. Producing potatoes with the water is not as high-yielding economically as other uses for water. And so if you want to produce spuds you probably don’t have enough cow manure, you certainly don’t want to pay for the amount of labour it involves to use manure, so you use an artificial fertiliser, produced using oil.

We are used to cheap food. In London last week, I saw a cooked chicken on sale for £2.50. And bizarrely, a banana is now cheaper in my local store than a spud.

A banana is cheaper than a spud!?!?!!! I know. Me too. Stunned!!!

The banana reaches our shores because of oil, but the spud reaches our shops because of oil as well - fertilisers, pumps for water, etc. And now the banana is cheaper than the spud. It is cheaper to bring a plant item from the other side of the planet than to grow a plant item in Ireland.

With oil reaching 100 dollars a barrel, we are now at the end of cheap food. The banana will no longer be so cheap, so we will buy more spuds, which will in turn increase the price of spuds. We need to react quickly to the problem. Naturally, we have enough money to struggle through the problem and the Africans will once again be screwed, no doubt.

However, you cannot deny that we are about to see a dramatic shift in agriculture, food production and the portion of our salaries that we will have to devote to food purchase.

The ‘psychological’ barrier I am waiting for is the spud for 10 dollars.

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