Palaeobotanist Jennie Andersson has analysed four soil samples for me, all from floor layers inside buildings at Medieval strongholds that me and my team have excavated in recent years. There’s one each from Stensö, Landsjö, Skällvik and Birgittas udde. Results were sadly not very informative.
“Overall the fossil and carbonised botanical material in the samples, as well as the recent unburnt material, is meagre … No carbonised cereals were found. Three of the four samples did however contain rather large amounts of unburnt bones and scales from fish plus jurpa, a blanket term för amorphous burnt organic material which may represent bread, burnt food, cooking waste or animal fat. Both the fish bones and the cooking waste probably originate in household cooking and waste management … The presence of burnt weeds such as goosefoot, bedstraw, smartweed and clover (Chenopodium album, Galium spp., Persicaria lapathifolia, Trifolium spp.), all of which thrive on nutrient-rich, sometimes slightly damp and open ground and around farms, tally well with what we may imagine would have been common in a castle bailey or around a farm yard where livestock and people tread about every day and share space.”