The Phase 1 Habitat Classification and associated field survey technique provide a standardised system to record semi-natural vegetation and other wildlife habitats. The approach is designed to cover large areas of countryside relatively rapidly. It presents the user with a basic assessment of habitat type and potential importance for nature conservation. Each habitat type/feature is identified by way of a brief description of its defining features. It is then allocated a specific name, an alpha-numeric code, and unique mapping colour. The Phase 1 classification comprises ten (A-J) broad high level categories: A: Woodland and scrub B: Grassland and marsh C: Tall herb and fen D: Heathland E: Mire F: Swamp, marginal and inundation G: Open water H: Coastland I: Exposure and waste J: Miscellaneous Amongst these, 155 specific habitat types are recognised, each having its own name, alpha-numeric code, description and mapping colour. There are 3 datasets which make up the Phase 1 Habitat Survey, habitat polygons, linear features and species target notes. The survey was carried between 1987 and 1989.