Melampyrum arvense L., Field Cow-wheat
Account Summary
Introduction, neophyte, here a definite mis-identification or recording error. European temperate, spread beyond its supposed native distribution by association with agriculture.
10 August 1970; Farrell, Ms L.; quadrat 7, limestone grassland at Monawilkin.
Growth form and preferred habitats
This annual hemi-parasite attacks the roots of grasses, cereals and a wide range of other species including Salix alba (White Willow). Despite being able to grow to a height of around 60 cm when occurring among tall grasses, having an attractive flower with dark pink lips and a terminal tuft of brilliant purple bracts, M. arvense has never been definitely recorded anywhere else in Ireland either before or since, and the current author (RSF) and RHN now believe the Fermanagh record is a definite field error or slip of the pen on the record card.
Formerly, M. arvense was an abundant pest weed in cornfields in places including the Isle of Man, the relatively large (5-6 mm × 2.7 mm) black seed discolouring flour. This was probably the case in the early part of the 19th century, when winnowing with a hand riddle was primitive, hard work and failed to separate weed seeds from grains of Corn. Following the introduction of more efficient threshing machines towards the close of the 19th century, M. arvense subsequently became an uncommon or even a rare and local seed-borne weed of arable agriculture in parts of S & SE England and the Isle of Man, especially on chalky soils (Salisbury 1964).
M. arvense survives in a handful of English VCs as a rarity of open, usually calcareous sites in grassland beside hedges and ditch banks, or in other very open, disturbed or eroding situations where it can avoid competition from more vigorous perennial species. Seed survives for about two years or perhaps longer in the soil and germination percentages are normally low, around 25% (Salisbury 1964; P.J. Wilson, in: Wigginton et al. 1999).
Fermanagh occurrence
There is a solitary record of Field Cow-wheat as listed above in the Fermanagh Flora Database, but it is almost certainly an error.
British and Irish status
Until recently, M. arvense was regarded as a diminishing English native cornfield weed, and a British Red Book rarity at that with only four scattered sites remaining (P.J. Wilson, in: Wigginton et al. 1999, p. 243)! It was one of the 41 species previously assumed native in Britain which Webb (1985) suggested were probably introduced by man and whose reassessment he advocated. It is now believed that M. arvense, which possesses a large black seed like a wheat grain, was originally introduced to Britain along with crop seed.
In parts of continental Europe, Field (previously called 'Common') Cow-wheat or 'Poverty Weed', is considered an archaeophyte. It was called the latter name because it discoloured the wheat or other flour and greatly lowered its value to the farmer. However the plant was first discovered in England in Norfolk by John Ray in 1724 (Salisbury 1964, p. 42) and its revised English status is therefore that of a rare and slowly declining neophyte (Preston et al. 2004).
There is no obvious reason why this crop seed alien could not have been introduced to suitable cereal growing areas of Ireland and it might have survived in disturbed marginal sites as has been the case in Britain. Nevertheless, the solitary existing Monawilkin record does not ring true since, in the view of RSF & RHN this upland, thin-soiled, rocky limestone terrain could not have supported cereal cultivation at any period in history.