Prehistoric, Environmental and Historical Context
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Sutton Hoo 10 Chapter 10 5/12/05 2:12 PM Page 361 Part III Context Sutton Hoo 10 Chapter 10 5/12/05 2:12 PM Page 362 Sutton Hoo 10 Chapter 10 5/12/05 2:12 PM Page 363 Chapter 10 Environment and site formation Martin Carver (with contributions by Charles French and Rob Scaife,and using specialist studies by Steven Rothera) Introduction which can be dug out in lumps (‘crag’). The soil above the The Deben valley runs through a region of sandy flat seaboard subsoil is generally 300–400 mm of well-mixed ploughsoil, territory known as The Sandlings (Figure 13; Plate 1:b). Between either still under the plough, or capped by tough springy turf. them its two rivers, the Deben and the Alde, give access to an Buried soil under the mounds has also been ploughed, and lies archipelago of promontories and islands with woods, pasture, some 250–400 mm thick. arable, meadows, marshland and fishing grounds (Scarfe 1986 The studies described in this chapter concern the and 1987; Warner 1996). The Sutton Hoo cemetery is situated on development of soils and vegetation at the site and its immediate the 33 m (100 ft) contour, on a sand terrace east of the River surroundings. The purpose of these studies was, first, to produce Deben, about 15.5 km (10 miles) upstream from the North Sea – an environmental history for the use of the land before the 10 km (6.25 miles), as the crow flies, from the nearest sea-coast mounds were built and, second, to produce a sequence of the at Hollesley. The river is tidal to Wilford Bridge, which lies about major soil-moving episodes to show how the extant deposits had a kilometre upstream from Sutton Hoo. Between the burial site formed. This information is used to help interpret the Prehistoric and the river is a flood plain about 300 m across (Colour Plates 1 sequence (Chapter 11) and the construction, reduction and and 2). It is now dry, being protected by a flood barrier, but it robbing of the mounds (Chapter 12). would previously have created brackish meadows, some parts of which could probably have floated a boat at high tide. Strips of Description of the investigations conifers have been planted in the nineteenth and twentieth Investigations 1945–83 centuries, to provide windbreaks and cover for game. In the The surface and sub-surface geology in the area of the Sutton flood plain are bands of beech and oak. Otherwise the Hoo site was studied by C. E. Everard in the context of the neighbourhood of Sutton Hoo is flat arable land, divided into British Museum programme of research of 1945–83 (SHSB I: ch. large fields interspersed with patches of now protected woods or 1). At this point, the River Deben was found to be 170 m wide at grassland. The Sutton Hoo barrow cemetery lies on one of these high water, and 24 m wide (and 0.6 m deep) at low water. patches of grassland. To its west, screening the site from the Everard concluded that the overall structure of the area had river, is Top Hat Wood; to the south and east are cultivated changed little since the sixth century. It was calculated that fields; to the north is a re-entrant valley, clad in bracken and the sea had fallen 1.6 m, but the land had also fallen overrun by rabbits. The weather is maritime: predominately dry, (tectonically) about 0.4 m, implying that the barrow site has with occasional blustery rain and strong prevailing north- had a net rise above sea level of about 1.2 m since the sixth easterly winds. century (SHSB I: 93–6). The subsoil beneath the cemetery is banded sand with The soil history and the vegetational sequence have dispersed lenses of pebbles, grit or small shells. The top, c.300 attracted the attention of environmentalists since the ship-burial mm, of sand is fine and very mobile when dry. Below this, the was rediscovered in 1939. Zeuner (1975) stated that the buried sand is concreted with silty clay into hard, striated deposits, soil beneath Mound 1 was the complete profile of a podzol, 1 m Sutton Hoo | 363 Sutton Hoo 10 Chapter 10 5/12/05 2:12 PM Page 364 Martin Carver thick, and the seventh century environment was a heather heath Floral survey (FR 9/6.1.2). This interpretation was revised by Geoffrey When the new campaign began in 1983 the Sutton Hoo site was Dimbleby (SHSB I: 48–77, fig. 11), based on sections cut during covered by bracken, up to one and half metres high, with the the British Museum campaign of 1966–71 into soil and subsoil occasional gorse bush. The mounds were barely visible, and beneath Mound 1, Mound 5 and Area A (Int. 11 – ‘Dr. rabbits were tunnelling everywhere. The rabbits were expelled Longworth’s Pit’). Dimbleby, using analysis of soil pollen, found and fenced off, and the bracken and gorse were removed by the buried soil was not a podzol, but was instead a brown earth cutting and mowing, as part of the initial management of the that had been cultivated, and he observed a change from a site. This at first created a ‘moth-eaten’ appearance; but in the pastoral to an arable regime during the life of the soil. first spring following the clearance in 1984, a large number of Cultivation was, stratigraphically, the last event before mound- species of grass and other plants appeared: an acid grassland building, with no intervening turf layer. Dimbleby was puzzled had emerged from its long captivity. A detailed survey of this that the Anglo-Saxons had apparently built mounds on a flora was intended, firstly, to provide a frame of reference for ploughsoil (SHSB I: 63–5; see below). It was noted that the site earlier flora, and, secondly, to map the patches of different had probably also been ploughed after the mounds were built surface soils revealed by different plant communities. (SHSB I: 61). In his survey, Rothera divided the site into 50 × 30 m areas, each given a letter code and a number of quadrats (with 0.5 m Investigations from 1983 sides) were randomly located within each area. For each The research targets of the 1983 campaign were to enhance the quadrat, the species present within it were recorded and a soil and vegetation history, and to address the problems of Domin cover-abundance value estimated for each. The survey what the land looked like before the mounds were built and was conducted in early June. Rothera identified 68 species: 20 what happened to them afterwards. It was decided to accept grasses, 35 herbs, 1 fern, 3 trees, 6 mosses and 3 lichens. The Dimbleby’s results on soil pollen from the site, and not to assemblage, which characterizes the potential plant population duplicate his investigation (FR 9/2.1). The vegetation sequence of the acid grassland, is summarized in Table 89. The full report would be enhanced by a section cut off-site, and by an is available in FR 9/6.1.5. The pattern of the flora also indicated examination of the present species population. The soil history the character of the soil beneath. An abundance of annual herbs would be studied by micromorphology, using the buried soil and grasses on a feature meant recent (<15 years) disturbance. for the history before mound-building, and the quarry-pit fills Archaeological digging had also helped maintain species for data on soil use after the mounds had been built. The soil diversity. To some extent the variation in plant cover helped history would be considered in conjunction with to map the history of the site, particularly the holes dug for archaeological studies of the processes of deposit formation, in archaeological and other purposes (see Chapter 2, p. 17, order to try to understand when and how earth had been Figure 6). moved on the site. This work also revealed the character of the acid grassland Three specialist investigations were undertaken: an that must have covered the site for much of its history. This inventory of plant species present on the site in 1984 by Steve grassland would be maintained by sheep grazing; only when the Rothera, which produced a floral survey (see below and FR sheep were no longer cropping the grass would the vegetation 9/6.1); an analysis of soil pollen by Rob Scaife, from a trench cut outgrow the nutrients, and the soil would podzolize and become off-site, which produced a vegetational sequence (Appendix 1, easy prey to invasion by heath. The easiest way to break up this chapter); and the micromorphological study by Charles heath would be to burn it off and plough it. This would create a French of samples taken off- and on-site, which produced great amount of podzolic sand, filling in all the hollows and important evidence for the formation of deposits and soils ditches, on top of which a crop and eventually pasture could (Appendix 2, this chapter). regenerate. The Sutton Hoo site itself, shorn of bracken, Running alongside these specialist investigations was the regenerated as a fine turf within five years. archaeological study of strata, recorded on site (see Chapter 3, p. 39). The relevant observations concerned the observation of On-site soil sequence the context interfaces that might signal changes in the soil The basic retrieval of palaeoecological data was through bulk- regime or cultivation, particularly in the sequences under sieving, flotation and grab sampling of all contexts excavated at mounds.