Some of the snowballs have a kind of animal energy. Not just because of the materials inside them, but in the way that they appear caged, captured.

For me looking, touching, material, place and form are all inseparable from the resulting work. It is difficult to say where one stops and another begins. Place is found by walking, direction determined by weather and season. I take the opportunity each day offers: if it is snowing, I work in snow, at leaf-fall it will be leaves; a blown over tree becomes a source of twigs and branches.

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.

Art for me is a form of nourishment. I need the land. I need it.

I have worked with this red all over the world - in Japan, California, France, Britain, Australia - a vein running round the earth. It has taught me about the flow, energy and life that connects one place with another.

I'm not a performer, in that I don't like the public, but I work in that respect.

The first snowball I froze was put in my mother's deep freeze when I was in my early 20s.