In field survey, some periods announce themselves by an abundance of artefacts, for example Roman ceramics in the Mediterranean and prehistoric flints in northern Europe. Others are elusive; among the least conspicuous in England is the early medieval period, when ceramics would seem to have figured little in material culture. When such wares did exist, tempered with soft material like grass, they are often destroyed by the plough and weathering Here the evidence, and its lack, is assessed, and means proposed to deal with it.The quantity and quality of early medieval pottery recovered by surface collection is sufficiently variable that many archaeologists are reluctant to accept isolated finds as anything more than 'background noise', preferring instead to examine the more visible elements defined by regional survey. But should isolated finds, recovered through systematic collection, really be regarded as 'rubbish data' in the light of recent debate concerning off-site scatters in other periods (e.g. Poley 1981; Bintliff & Snodgrass 1988; Schofield 1987)? It is towards this question that the paper is directed. 1 Three questions arise: Why are there regional variations in the quantity of pottery visible on the field surface? Are we justified in our tendency to focus attention more on pottery concentrations than on isolated finds? How might the 'rubbish data', the isolated finds recovered by systematic collection, be made both useful and usable? In order to tackle these questions we need to establish a fuller understanding of what early medieval (i.e. pre-Conquest) pottery distributions represent in terms both of the quantity of pottery recovered and of its distribution within 2 3 the landscape. The use of results from excavation is seen as a key factor in this respect and a valid 'control' for surface investigations.
Causes of variation in surface distributionsA number of well-documented factors determine the quantity of early medieval pottery recovered by surface collection: the amount of pottery in circulation; the nature of the pottery; landscape taphonomy; use and discard behaviour; the scale and intensity of collection and agricultural activity. These will be considered in two sections, looking first at visibility and second at formation processes and the collection strategy.