I have to understand the nature of change. And I cannot just work with stone or the more permanent materials. I need to work with leaves and ice and snow and mud and clay and water and the rising tide and the wind and all these.

I soon realised that what had happened on a small scale cannot necessarily be repeated on a larger scale. The stones were so big that the amount of heat required was prohibitively expensive and wasteful.

People do not realise that many of my works are done in urban places. I was brought up on the edge of Leeds, five miles from the city centre-on one side were fields and on the other, the city.

I think that I'm always trying to get beyond the surface appearance of things, to go beyond what I can just see.

I want to get under the surface. When I work with a leaf, rock, stick, it is not just that material in itself, it is an opening into the processes of life within and around it. When I leave it, these processes continue.

Ephemeral work made outside, for and about a day, lies at the core of my art and its making must be kept private.

Sometimes you need to stop doing something to really see it afresh.