Clay | A soil type described by Tom Stevenson (2011) as ‘a fine-grained argillaceous compound with malleable, plastic characteristics and excellent water-retention properties. It is, however, cold, acid, offers poor drainage, and, because of its cohesive quality, is hard to work. An excess of clay can stifle the vine’s root system, but a proportion of small clay particles mixed with other soils can be advantageous.’

Bibliography

Tom Stevenson (2011) The Sotheby’s Wine Encyclopedia 5th Edition by Tom Stevenson (Dorling Kindersley, 2011), p.17-19.