plant macrofossils: the Trust and archaeobotany

On the 1st May 1753, Swedish botanist, zoologist and physician Carl Linnaeus – ‘the father of taxonomy’ – published his famous book Species Plantarum. This was the start of plant taxonomy adopted by the International Code of Botanical Nomenclature for algae, fungi and plants. Plant taxonomy is a science which identifies, describes, classifies and names plants. Val Fryer is a specialist in archaeobotany and palaeoethnobotany, and she produces reports for the Trust on the archaeological evidence of organic plant material from our sites – that is, the remarkable, large-scale evidence which can be extrapolated from very tiny remains (plant macrofossils) and then interpreted. Plant macrofossils are tiny and they are extracted from soil samples which we take from archaeological sites: their study involves what must be the tiniest examples of archaeological evidence…

Trust senior archaeologist Howard Brooks says: ‘Archaeobotany is one of the newer fields of study in archaeology. It does exactly “what it says on the tin”: it is the study of ancient botanical remains’. Most archaeobotanical samples are taken by our excavation team from suitable contexts such as pits and ditches on a site. The samples are brought back to the Trust’s HQ here at the Roman circus centre in large plastic bags or containers. We wash the samples through a sieve to extract tiny remains of seeds, cereal grains and plant fragments of wild and cultivated plants. The specialist will then study these fragments under a microscope. The fragments show which crops were being grown in the vicinity and what the local environment was like in a given historical period. However, the Colchester district is not an area where particularly rich archaeobotanical remains are found.

Archaeobotany is the study of macrofossils of different elements and different parts of plants/seeds/grains/etc, based on plant taxonomy. ‘… The combination of genus and specific epithet into a single phrase called the “species” is the basic component of botanical nomenclature. There are finer divisions such as cultivar, variety, and subspecies which describe minor variations, but “species” is the level at which gardeners operate …’ (from http://tomclothier.hort.net/page36.html ; ‘genus’ is the Latin word for type or group). One of our most interesting assemblages of plant macrofossil evidence must be from the Stanway aristocratic burial site near Colchester.

The Stanway aristocratic burial site is a site which the Trust excavated between 1970 and 1997 and it is of national archaeological importance. It consists of five funerary enclosures which had been used for the burials of the native aristocracy in the Late Iron Age and the early Roman period: the burials included the ‘Warrior’s grave’ and the ‘Doctor’s grave’, which produced the famous gaming-board, kit of medical instruments and strainer bowl. Specialist Patricia Wiltshire made a very important palynological contribution to our report on the site with her identification of traces of artemisia (wormwood) in the strainer bowl. Val Fryer is currently studying the plant macrofossils from our recent excavation of another remarkable site at Stanway, in 2015, which included the sites of two Iron Age enclosures which are associated with the Stanway aristocratic burial enclosures, although at a distance. Her results will be included in our site report.

The archaeobotanical evidence from the Trust’s excavation of the Stanway aristocratic burial site is fascinating. Val Fryer identified over 50 plant species from Middle Iron Age, Late Iron Age and early Roman contexts on the site, plus other categories of remains.

The plant macrofossils from the Stanway aristocratic burial site are listed in a table and the results are summarised below *. In Val Fryer’s discussion of the results, she observes that there were a few remains of wetland plants. ‘… Charcoal occurred in variable quantities, together with other indeterminate charred plant macrofossils, and charred and vitrified material thought to be mainly of plant origin… The material from these samples is thought to indicate settlement activity. The small coal fragments present are likely to be intrusive, relating to 19th-/20th-century steam ploughing.
The remaining samples were from contexts associated with burials or their enclosures and included wood charcoal with charred fragments of indeterminate tubers, rhizomes and monocotyledonous stem fragments, moss stem fragments and fruits and seeds of heath grass (Danthonia decumbens) and the herb blinks (Montia fontana). This points to damp, partly flushed, acid grassland, presumably growing locally on leached gravel-based soils. Possible interpretations are that the charred plant material represents plants uprooted for kindling or vegetation charred in situ beneath a pyre …’. The charred plant material might represent charred residues from burnt turves, which seem to have been associated with high-status burials of the period or it might have been used in the construction of pyres.

These results are published in ‘The plant macrofossils’, by Val Fryer, in Stanway: an elite burial site at Camulodunum, by Philip Crummy et al (Britannia, Monograph series, no 24, 2007; pages 384-399). The International Code of Botanical Nomenclature for algae, fungi and plants is published online at www.iapt-taxon.org/nomen/main.php?page=pre . Read more about Linnaeus at www.britannica.com/biography/Carolus-Linnaeus . Species Plantarum is reproduced online at www.biodiversitylibrary.org/item/13829#page/1/mode/1up . Read more about the Stanway burial site at www.archaeologyuk.org/ba/ba99/feat3.shtml and about our recent Stanway site on this web-site at www.thecolchesterarchaeologist.co.uk/?p=23904 .

The image shows the title page of Species Plantarum (this image is in the public domain and it is published online on https://commons.wikimedia.org : the source is the Biodiversity Heritage Library online).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

* The nomenclature here includes the Latin name and the common name of the plant (the Latin name can consist of the genus and species names plus an epithet); spp. = species, ie all species within a genus; sp. = subspecies; ‘indet.’ = indeterminate; L. = Linnaeus, ie classified by Linnaeus in Species Plantarum.

Cereals (in the form of grains, rachis nodes and glume bases): cereal indet.; Hordeum sp. (barley); Hordeum vulgare (six-row barley); Hordeum/Secale cereale (barley/rye); Triticum sp. (wheat); Triticum spp.; Triticum dicoccum Schubl. (emmer); Triticum spelta L. (spelt wheat); avena (oats); large Poaceae (grasses); Poaceae indet. (grasses).
Dryland herbs (weeds/grassland): Asteraceae (daisy); Atriplex (saltbush); Brassiaceae (includes mustards, cabbages, broccoli, turnips, cresses); Bromus sp. (brome grass); Bromus mollis/secalinus (a grassy weed which infests winter rye and winter wheat); Chenopodiceae (goosefoot, also includes beets and spinach); Chenopodium album L. (fat hen); Fabaceae indet. (legume/pea/bean); Falllopia convolvulus (wild buckwheat); Galium aparine L. (goose grass); Medicago/Trifolium (clover); Persicaria p. (knotweed); Plantago lanceolata L. (plantain); Polygonaceae indet. (includes buckwheats); Polygonum aviculare L. (prostrate knotweed); Potentilla sp. (cinquefoil); Rumex acetosella L. (sheep’s sorrel); Stellaria graminea L. (stitchwort); and Vicia/Lathyrus sp. (vetch).
Wetland plants: Carex sp. (sedge); Eleocharis sp. (spikesedge); and Montia fontana (blinks or water chickweed).
Trees and shrubs: charred nutshell fragments of Corylus avellana (hazel) and fruitstones of Crataegus monogyna (hawthorn) and Prunus spinosa (sloe); P. domestica; P. spinosa; Quercus sp. (oak); and Sambucus nigra (elder).
Heathland plants: Danthonia decumbens (heath grass).
Other plant macrofossils: charcoal from a variety of trees; charred root/rhizome/stem; floret of ericaceae indet. (heather); indet. buds; indet. fruit stone fragments; indet. seeds; indet. tuber fragment; moss stem fragments.
Other material: black porous ‘cokey’material, black tarry material; bone; pottery; siliceous globules; small coal fragments; and charred and vitrified material of plant origin.

.