Pastinaca sativa L., Wild Parsnip
Account Summary
Introduction, archaeophyte, an infrequent casual escape from cultivation, probably locally extinct. Eurosiberian temperate, but very widely naturalised.
1900; West, W.; roadside or waste ground at Drumskew Td, W of Enniskillen.
Growth form and preferred habitats
The fleshy, white taproot of this large, biennial, monoecious, yellow-flowered species has been in cultivation as a culinary vegetable grown from seed throughout the Mediterranean basin and temperate Europe since the Classical Greek period; even earlier than this it was used for animal fodder. Good edible selected forms were first developed around the Middle Ages (Zohary & Hopf 2000), and as the food value of parsnip exceeds any other vegetable except potato, and it is very easy to produce, it should be more extensively grown than it is.
Escapes of the plant from cultivation in fields or gardens tend to revert to the 'wild condition', with tough, dry, much thinner roots than the usual cultivated rootstock (Smith 1976). The erect stem can be up to 180 cm tall and it may be either hollow or solid, its surface furrowed, terete or angled. It may also vary greatly in hairiness, either having sparse, short hairs, or numerous long, flexuous ones. Variation in the species is considered sufficient for three subspecies to have been recognised recently in Britain (see below).
Wild Parsnip typically occurs in unmanaged grassland, roadsides and other waste or rough ground near habitation, especially on chalk and limestone soils, or near the coast (Sell & Murrell 2009).
Fermanagh occurrence
There is just the single record detailed above in the Fermanagh Flora Database as a roadside garden escape near Enniskillen dated over a century ago.
Variation
Since 2009, three subspecies are distinguished in Britain, if not in Ireland (Sell & Murrell 2009; Stace 2010; Parnell et al. 2012). The form escaped from cultivation is subsp. sativa, with its swollen rootstock that is not found in the other two subspecies. Subsp. sativa also has sparse, short, straight hairs on its stems and leaf upper surfaces. The form most like this is subsp. sylvestris (Mill.) Rouy & Camus which has long, soft, flexuous hairs on its stems and upper leaf surfaces grey-hairy. The third form, subsp. urens (Req. ex Godr.) Čelak., has stems terete, with short straight hairs or nearly glabrous (Sell & Murrell 2009).
Irish occurrence
In Ireland, Wild Parsnip is an infrequent casual weed of rough grass on roadsides, waste ground and in old quarries. Unfortunately, all of these are places where people frequently 'fly tip' garden rubbish. P. sativa has been recorded at least once over the years from 33 of the 40 Irish VCs (Cat Alien Pl Ir). The New Atlas map of it for Ireland plots just 13 hectads with post-1986 records. All but two of the sites plotted are coastal, undoubtedly reflecting this species preference for sandy, neutral and/or calcareous ground.
Fossil record
Evidence from pollen and fruit fossils in Britain is sparse, but nevertheless it shows P. sativa has been present right back into the early record of the Cromer Forest Bed series and in all interglacials since then, plus in the last glacial period, the Devensian (or Weichselian). As Godwin (1975) commented, "It thus appears that P. sativa is a long-persistent native, at least in southern England where most of the fossil records come."
British occurrence
Wild Parsnip is common on calcareous soils in lowland Britain, particularly S of a line between Newcastle and Preston, and it is even more frequent if we draw the line from the mouth of the River Humber to that of the Severn. In addition, it does occur north of these two lines of demarcation, chiefly in coastal or disturbed urban sites; in these northern areas, it is recognised as being an alien. Based on its fossil record, south and east of the Humber-Severn line P. sativa is traditionally believed to be a native species (Godwin 1975; New Atlas).
There are three subspecies in Britain: subsp. sativa is usually recognised to be an escape from cultivation, whereas subsp. sylvestris is the form most usually met in the SE of England and in S Wales and is considered native in those areas. The third subspecies, subsp. urens, is confined to the Suffolk coast, where it just might be native, although its main distribution is in S, C & E Europe (Sell & Murrell 2009).
It is also known that in recent years, P. sativa has sometimes been accidentally introduced as a seed contaminant in 'wild flower seed mixtures' when roadside verges and banks are resown by Local District Council Roads Departments.
Seed survival is rather impressive: in a buried seed experiment, germination occurred after 17 years incorporation at a depth of 120 cm (Toole & Brown 1946).
European and world occurrence
Wild Parsnip is widespread throughout temperate Europe except the extreme north, plus in western Asia. However, as is the case in England and Wales, because the plant is widely naturalised, its native range is difficult or impossible to discern. The cultivated form, subsp. sativa, has been introduced to N & S America, S Australia and New Zealand, where it regularly escapes from gardens into rough ground habitats (Hultén & Fries 1986, Map 1428).
Uses
Apart from being cooked and used at table as a nutritious vegetable, Parsnip has also been used as a quality fodder for fattening pigs; mixed with bran it has been fed to horses, and it has also been given to cattle, including milking herds (Grieve 1931). The roots (ie rootstocks) contain starch and sugar and have been brewed with malt to make beer, wine and spirits.
In the past, herbal medicine has used P. sativa to treat cancer, consumption, asthma and similar diseases. It has also been claimed to have cleansing and opening qualities, provoking urine, easing pain and stitches in the sides, expelling wind from the stomach and bowels and also useful for colic (Culpeper 1653; Grieve 1931).
Threats
None.