Four-post structures

Four-post structures in later prehistory are often presumed to have been elevated granaries. Some consisted of 5–9 posts (Cunliffe 1991, fig. 15.2), and might also have been fodder ricks, general storage structures, chicken coops, menstrual huts, or platforms for the exposure of the human dead. Older (and less likely) interpretations include watchtowers, ‘fighting platforms’, and even elevated huts (Challis and Harding 1975: 150-1).

At Sutton Common, hundreds of postholes were found within Enclosure A, from which at least 115 four-poster structures could be identified with some certainty, with another 30–40 possible examples (Chapman, Fletcher and Van de Noort 2007: 115). Many appeared to be aligned in broadly north-south or east-west rows of 4–6 structures. Several six and eight-post structures were also identified. Flat-bottomed oak posts were mainly utilised for their construction, with a few Scots pines. Unfortunately, relatively few of the four-post structures were fully excavated or sampled for palaeo-environmental remains, and so the function of them as granaries must remain inferential. Most wood from the interior of Enclosure A was too degraded for dendrochronological dating. For some inexplicable reason, no wood or charred grain from the four-poster postholes was submitted for radiocarbon dating. This might have allowed chronological groupings of four-posters to be identified, but it unfortunately remains unclear how many structures were built and used at any given period – it must surely have numbered dozens at the very least. This might indicate crop storage beyond the household level and may potentially have represented the accumulated stores of an entire community. The possible groups of structures might have represented contributions by individual households and farmsteads, or lineages and clans. What is still unknown is where all the earlier Iron Age domestic settlements contemporary with Sutton Common were.

The excavated postholes of several Iron Age four-post structures at Sutton Common produced large quantities of carbonised cereals, mostly wheat and oats (Hall and Kenward 2007: 126). The grain to chaff and wheat to barley ratios sometimes suggested wheat being stored for human consumption, but other examples seemed to indicate mixed crops or maslins for animal fodder. In many older accounts it was proposed that charred grain in postholes was derived from fires in the structures above (either accidental or deliberate firing), but at Sutton Common it was noted that some charred remains were in the initial fills of the postholes, in some instances below the waterlogged remains of the posts themselves. This cannot be explained by above-ground conflagrations. It has thus been suggested that these were primary deposits, perhaps deliberate apotropaic offerings designed to bring good luck and ensure the safety of the stored crops (Van de Noort 2007: 133). Similarly, just one four-post structure at Sutton Common produced 18 saddle quern fragments from two of its postholes (Watts 2007: 145-6), and in addition to a prosaic function as post packing this might perhaps suggest deliberate deposition linked to ideas of fertility.

The rest of South Yorkshire provides a marked contrast to Sutton Common. Four-post structures, but mostly single examples, have been identified within Enclosure E1 and near Enclosure E8 at Redhouse Farm, Adwick-le-Street (Meadows and Chapman 2004: 6, fig. 4; Upson-Smith 2006: 6, fig. 3), and possibly at Roebuck Hill, Jump (Robinson and Johnson 2007: fig. 6). Several four and six-post structures were identified at High Street, Shafton (Burgess 2001a; Howell 1999, 2005); and some four-post structures may have continued in use well into the Roman period, as at Billingley Drive, Thurnscoe (Neal and Fraser 2004: 24, fig. 14). Otherwise however, they seem to have been relatively rare within the region.

Research questions

  • What were four to six-post structures, and were they associated with grain storage? Did they have other uses? Is grain storage merely an assumption?
  • If used for grain, what storage capacity might have been represented by four and six-post structures? Did these represent household production, or more intensive/large-scale cultivation and crop processing?
  • When were four and six-post structures adopted in South Yorkshire? Was it a late Bronze development, as 14C dates from sites such as South Elmsall (McNaught 1991) in West Yorkshire suggest? When did they go out of use?

Priorities and implementation

  • The function of four-poster structures should be explored wherever possible, using detailed sampling and palaeo-environmental analyses to look for evidence of grain, insect pests of stored grain, remains of plants associated with hay or fodder, pests and parasites of fowl, and other such indicators;
  • Every attempt must be made to obtain multiple dates from groups of four-post structures. These were not unimportant ancillary structures. If a site produced evidence for many four-post structures of approximately the same date, this may indicate storage and social relationships beyond the household level. Similarly, a wide spread of dates may simply indicate that one or two structures were in use at any one point in time.