ULAS
University of Leicester Archaeological Services

Plants and seeds - investigating ancient rubbish

Photograph of archaeologists taking environmental samples

During excavations in the town archaeologists take samples of soil from the pits, hearths, ovens and other features so that it can be sieved to find small seeds, bones and other remains.  Sieving is carried out in a tank made from an oil drum and the delicate remains are carefully separated from the soil in running water so that they can be identified under the microscope.

Rubbish pits:
Rubbish pits are also a good source of evidence because they often contain charred remains which do not decay, mixed with animal bones and pottery which can be used to date the material.  This type of rubbish may contain accidentally spilled cereal grains burnt in the cooking hearth, then dumped in a pit with other rubbish such as meat bones to show the foods consumed.  Other features such as hearths and ovens may contain charred cereal remains and seeds to show how food was processed.

Charred plant seeds from Roman hay/fodder (Causeway Lane).
Left, Ox-eye Daisy. Right, Crested Dog's tail grass

Cesspits:

Cesspit in section from Sanvey Gate

Before the widespread use of sewers, cesspits were dug in which sewage was dumped and these pits are often a rich source of evidence because the minerals in the sewage cause the remains to become semi-fossilised.  These pits may also contain coprolites (semi-fossilised excrement) and tests can reveal the presence of the eggs of gut parasites, which together with the preserved maggots of latrine flies leave no doubt about what was being dumped in the pit.  Cesspits often contain fruit stones, fruit pips and chewed fish bones which, considering where they are found, show the foods which had been eaten.

Remains from sewage in cesspits: Above left, egg parasite of whip worm found in the human gut. Centre, Fish bones, some being distorted by chewing (medieval, The Shires I). Above right, Fly puparia.

Sampling the town defences:

The town ditch was found to be waterlogged with organic remains preserved in the sediments. In the main photo, archaeologists are sampling a column of layers within the town defensive ditch using metal tins.

The profile of the ditch is highlighted with the white line. To the right is the position of the pollen sample in the sequence of ditch fills. The soil will be analysed for pollen and seeds by a specialist and this will tell us about the environment at the time the ditches were in use. In addition to this we took pollen samples from a buried soil under the defensive rampart, which will indicate what the area was like just before the Roman defences were constructed. In the photos below are some of the finds we get from this kind of sampling, including oak pollen, elder seeds and snails.

Roman food:
Foods remains from Roman Leicester range from barley and spelt wheat, legumes and leaf beet, fruits such as sloe, wild plum and apple. While coriander, fig and lentil may have been imported, opium poppy and columbine may be garden plants.  Other foods included fish such as herring and eels and oysters. The oyster shells are thought from their size, shape and infestations to have been brought from the Essex coast. The origin of recent finds of oyster shell is to be investigated.

Charred cereal grains (mostly wheat and rye). Centre, close up of rye grains. Right, wheat grains

Medieval food:

Remains from numerous cesspits and rubbish pits show that there was intense occupation in the 12-13th century in the Shires area.  More fruits included grape, blackberry, damson, plum, apple and pear, and vegetables included pea, bean and leek.  The cereals included bread wheat, which is used today, and rivet wheat which was not so good for bread making but could be used for pottage (thick soup or stew), a medieval staple food.  Rivet wheat first appeared in Late Saxon times and its introduction is under investigation. Remains of more large sea-fish were present showing the fishing of deeper waters than in the Roman period.  Further investigations are in progress. Recent excavations will add to this evidence of diet and trade, and help to show the character of activity and occupation in the north-east quarter of the historic town.