There was a time when farmers were very conscious of using a frost mold to do their winter cultivations for free. Now, too often, a power harrow is used to “force a tilth” in a rush in August/September to get the next autumn sown crop in. With the switch autumn cropping has come a reliance on power input. However, not with all farmers. Some have long switched to reduced cultivations, some to one pass only. In the USA, over half of all crops are put in with “zero till”.
At present, diesel prices are low. The deal this week with Iran (and its nuclear leverage) will allow their oil onto the global market in much larger quantities. That will help keep the price of diesel down.
Despite that breathing space, it may be as well to remember that experience on putting regular dressings of compost made from “wastes” onto heavy land soils can reduce power inputs by over 60 %. That is sustainability.
Bill Butterworth 20 January 2016