Monday 18 June 2018

Feral Plum (Prunus domestica)


FERAL PLUM (Prunus domestica)
Family: Rosaceae

Alien introductions   
Bullaces (Prunus domestica subsp. insititia), Damsons (Prunus domestica subsp. insititia), Greengages (Prunus domestica subsp. italica) and Cherry plums (Prunus cerasifera) and the classic domestic plums (Prunus domestica subsp. domestica) appear to have been introduced into Britain as cultigens (Woldring 2000; Zohary et al. 2012: 140-143). However, they are now found growing in hedgerows right across the British Isles, sometimes self-sown and naturalised, but more often planted by earlier generations of rural cottage gardeners and land-owners (for distribution maps see Online Atlas of the British and Irish Flora). Pliny the elder in his ‘Historia Naturalis[i] (c. AD 77-79) writes that plums were initially introduced into Greece and Italy from Syria (see additional references in Jashemski et al. 2002: 148-149; Woldring 2000: 536, 548). They were introduced into central and northern Europe much later, probably during the Crusades, when they were once again imported from the Near East; for example, the ‘damson-plum’ (or ‘damascene’) was apparently introduced into Europe from Damascus or Jerusalem by the Duke of Anjou after the fifth crusade (1198-1204; Davidson 2014: 246). In this regard, however, it is intriguing that the name ‘bullace’ in English is cognate with its Celtic counterparts: e.g., the Welsh: ‘bwlas’ (Geiriadur Prifysgol Cymru (A dictionary of the Welsh language) 1953), Old Breton: ‘bolos’ (Troude, 1842: 437) and Irish ‘bulistair’ (O’Reilly 1821), each of which it is assumed has origins predating the crusades.

Complex inter-relationships   
Bullaces (including damsons), Greengages and the many forms of domestic plum are all assignable to one of three subspecies of a single species: Prunus domestica, and they are fully inter-fertile (Faust 2011; Watkins 1995; Woldring 2000). However, they are often difficult to distinguish from the various Cherry plums (for examples of the range of fruit morphologies see Botu et al. 2012; Faust 2011: figure 1). Indeed, after outlining some of the complex inter-relationships between the many species of wild and cultivated plums in Europe and beyond, Zohary et al. (2012: 142) make the following statement: 
In conclusion, the 6x P. domestica plums seem to be closely related to the 2x, 4x and 6x P. cerasifera. Together they form what seems to be a P. cerasifera – P. domestica polyploid crop complex. If wild forms of 6x P. domestica existed in south-east Europe and/or south-west Asia prior to domestication (and they probably did), they should be regarded as the ancestral stock for the development of the fruit crop. However, if as some botanists believe, domestica plums evolved only under cultivation the plausible principal progenitor is the P. cerasifera aggregate.

Budding and grafting 
To maintain their favoured varieties, those importing the plums would have had to propagate them vegetatively (Webster 1995). They could have done this either firstly by transplanting the saplings with carefully wrapped root-balls and, if necessary, already budded and grafted with the desired varieties, or secondly by importing freshly-cut shoots of the cultivar steeped in water from which they could then quickly excise bud-grafts or cut scions for grafting onto rootstocks of compatible wild species, just as farmers in Turkey do today with vast numbers of the plum, cherry, pear and apple-trees growing in the wild (Bolat et al. 2017). Of the native trees of Britain available as rootstocks, apparently the most compatible would have been Blackthorn (Prunus spinosa).

Feral forms and survivors   
Since being introduced imported plums have seeded themselves in many locations across the British Isles, most commonly in southeastern England, but occasionally as far north as southern Scotland. Propagation by seed is likely to have selected for the re-emergence of some archaic, wild-type characteristics including sharper flavours. However, many of the more ancient fruit trees in our hedgerows are venerable survivors either from the once carefully husbanded gardens of long–forgotten cottages, or from the hedgerow planting of fruit trees by large estates, which thereby provided fruits for their tenants without needing to devote land to orchards. Such trees sometimes represent domestic varieties that are today rarely cultivated. 

Feral forms of plum are seldom spiny and they have ‘showy’ flowers with pedicels that have, at most, a few sparse hairs. The fruits are lop-sided with a marked, one-sided groove and the flesh separates cleanly from the smooth, flattish stone; they are usually sweet and juicy,

Uses 
All plum varieties have fruits that are (or were) traditionally eaten fresh, roasted or stewed, dried as ‘prunes’, or used to prepare fruit leathers (Plants For A Future [PFAF] database; see also Lim 2012: 463-475). In Turkey certain varieties are also eaten while still green (‘can eriği’, green plum) and while the stone is still soft so that the whole fruit can be eaten, normally with a pinch of salt[ii].

As with cherry trees, the congealed gums that exude copiously wherever the bark is wounded are reported to be both edible and nutritious. In all the fruits the ripe kernel within the stone contains the bitter, cyanogenic glucoside called amygdalin (Bolarinwa et al. 2014), and is poisonous unless thoroughly crushed and roasted (see entries for Blackthorn and Bird Cherry).

Prehistoric and historic usage
Many authors have commented on the fact that the morphological features of Prunus fruitstones are useful for distinguishing between species and varieties (Depypere et al. 2009; Woldring 2000; Ucchesu et al. 2017), and as the stone (or endocarp) is the part of the fruit that most commonly survives on archaeological sites this enables identifications beyond genus level to be made. As Woldring (2000: 537-538) notes:
“Of all the identification marks, the features of the stones seem the most stable characteristics.” And he cites Hedrick (1911), who states: "In describing the several hundred forms of plums for The Plums of New York, the stone has been quite as satisfactory if not the most satisfactory, of any of the organs of this plant for distinguishing the various species and varieties".

Ucchesu et al. (2017) use comparative morphometric studies of fruitstones from modern populations on Sardinia and ancient waterlogged specimens from the site of Santa Giusta (dated to the Phoenician and Punic periods, 6th-2nd centuries BC) to identify wild (Prunus spinosa) and domestic (Prunus domestica) species. Their findings have an added significance because they are able to conclude that the Prunus stones found at Santa Giusta are evidence of the earliest cultivated plums on Sardinia and, more importantly, also in Italy.

A majority of archaeological records for Prunus are Roman and post-Roman[iii], although there are earlier sites in Europe where remains of plums (e.g., Cherry plums, Damsons) have been identified (see Kroll 1998: 41; Faust 2011: 158-159, table 2; Ucchesu et al. 2017: table 1; Zohary et al. 2012: 142)[iv]. There are also early pictorial depictions of plums, for example in Roman wall paintings. Jashemski et al. (2002: 148-149) describe images of plums found at Pompeii: in the House of the Fruit Orchard[v], where several trees with different coloured fruits are illustrated; in the House of Trebius Valens[vi], in which a bird with two purple plums are shown (Jashemski et al. 2002: figure 133); and on buried fragments of a wall painting in the House of the Gold Bracelet[vii] that shows a branch with two yellow plums (Jashemski et al. 2002: figure 134). Also, at the nearby ancient site of Oplontis[viii] in the Villa of Poppaea there is a wall painting of quinces and blue and purple plums in a glass bowl (Jashemski et al. 2002: figure 88).

Bibliography

Bolarinwa, I.F., Orfila, C. and Morgan, M.R.A. 2014. Amygdalin content of seeds, kernals and food products commercially-available in the UK. Food Chemistry 152: 133-139.

Bolat, I., Ak, B.E., Acar, I. and Ikinci, A. 2017. Plum culture in Turkey. Acta Horticulturae 1175: 15-18.

Botu, M., Tomić, L., Cvetković, M., Gjamovski, V., Jemrić, T., Lazović, B., Ognjanov, V., Pintea, M., Sevo, R., Achim, G., et al. 2012. Balkan Pomology: Plums. SEEDNet's WG for Fruit and Vitis, 2012: Ljubljana.

Davidson, A. 2014. The Oxford Companion to Food. 3rd Edition. Oxford University Press, Oxford.

Depypere, L., Chaerle, P., Breyne, P., Vander Mijnsbrugge, K. and Goetghebeur, P. 2009. A combined morphometric and AFLP based diversity study challenges the taxonomy of European members of the complex Prunus L. section Prunus. Plant Systematics and Evolution 279: 219-231.

Faust, M. 2011. Origin and dissemination of plums. In Janick, J. (ed.), Origin and Dissemination of Prunus Crops: Peach, Cherry, Apricot, Plum, Almond. International Society for Horticultural Science (ISHS), Leuven. pp. 139-186. http://www.actahort.org/chronica/pdf/sh_11.pdf [accessed: 06.04.18]

Geiriadur Prifysgol Cymru (A dictionary of the Welsh language) 1953: http://geiriadur.ac.uk/gpc/gpc.html?bwlas [accessed: 03.04.18]

Greig, J. 1995/6. Archaeobotanical and historical records compared—a new look at the taphonomy of edible and other useful plants from the 11th to the 18th centuries A.D. Circaea 12(2): 211-247.

Hendrick, U.P. 1911. The plums of New York. J.B. Lyon, Albany. [full text available at: https://archive.org/details/plumsofnewyork00hedrrich]

Jashemski, F.W., Meyer, F.G. and Ricciardi, M. 2002. Plants: Evidence from Wall Paintings, Mosaics, Sculpture, Plant Remains, Graffiti, Inscriptions and Ancient Authors. In Jashemski, F.W. and Meyer, F.G. (eds.), The Natural History of Pompeii. Cambridge University Press, Cambridge. pp. 80-180.

Kroll, H. 1998. Literature on archaeological remains of cultivated plants (1996/1997). Vegetation History and Archaeobotany 7: 23-56.

Lim, T.K. 2012. Edible Medicinal and Non-Medicinal Plants. Volume 4, Fruits. Springer, Netherlands.

Online Atlas of the British and Irish Flora. Botanical Society of Britain & Ireland. https://www.brc.ac.uk/plantatlas/ [accessed 05.04.18]

O’Reilly, E. 1821 An Irish-English dictionary to which is annexed a compendious grammar. 2nd Edition. Minerva, Dublin.

Plants For A Future (PFAF). http://www.pfaf.org/ [accessed 05.04.18]

Troude, A.E. 1842. Dictionnaire français et celto-breton. Lefournier, Brest.

Ucchesu, M., Sarigu, M., Del Vais, C., Sanna, I., d’Hallewin, G., Grillo, O. and Bacchetta, G. 2017. Finds of Prunus domestica L. in Italy from the Phoenician and Punic periods (6th-2nd centuries BC. Vegetation History and Archaeobotany 26: 539-549.
van der Veen, M., Livarda, A. and Hill, A. 2008. New plant foods in Roman Britain – dispersal and social access. Environmental Archaeology 13(1): 11-36.

Watkins, R. 1995. Cherry, plum, peach, apricot and almond: Prunus spp. (Rosaceae). In Smart, J. and Simmonds, N.W. (eds.), Evolution of Crop Plants. 2nd Edition. Longman Scientific & Technical, Harlow. pp. 423-429.

Webster, A.D. 1995. Temperate fruit tree rootstock propagation. New Zealand Journal of Crop and Horticultural Science 23(4): 355-372.

Willcox, G. 1977. Exotic plants from Roman waterlogged sites in London. Journal of Archaeological Science 4: 269-282.

Woldring, H. 2000. On the origin of plums: a study of sloe, damson, cherry plum, domestic plums and their intermediate forms. Palaeohistoria 39-40(40): 535-562.

Zohary, D., Hopf, M. and Weiss, E. 2012. Domestication of Plants in the Old World. The origin and spread of domesticated plants in Southwest Asia, Europe, and the Mediterranean Basin. 4th Edition. Oxford University Press, Oxford.




[i] Pliny the Elder. Historia Naturalis. English translation by H Rackham: Loeb Classical Library (1950).
[iii] For more details on Roman and post-Roman sites with Prunus remains see references in Greig 1995/6; Kroll 1998, Faust 2011; Ucchesu et al. 2017; van der Veen et al. 2008; Willcox 1977; Zohary et al. 2012).
[iv] The criteria used to identify the Prunus species on sites that pre-date the Roman period are not given in these secondary sources.

No comments:

Post a Comment