Lemnaceae
Lemna minor Linnaeus; and other species
duckweed
cosmopolitan except for polar regions and tropics
Allegedly once a cure in the Highlands for headaches and inflammation,^14 a
record ofLemna minor in Leitrim to bathe a swelling^15 may be confirmatory
evidence of that. In Cavan,^16 however, and in some other unidentified part of
Ireland^17 the plant’s value has been as a tonic to cleanse the system. ‘Duck’s
weed’ was also formerly a popular healing herb in Lewis in the Outer Heb-
rides for some unspecified purpose.^18
Juncaceae
Juncus inflexus Linnaeus
hard rush
Europe, western and central Asia, Macaronesia, northern and
southern Africa, Java; introduced into eastern North America,
Australasia
It may or may not have been mere chance that it was Juncus inflexus that
proved to be in use in parts of Ulster at one time for jaundice.^19 Usually, folk
records refer only to ‘rushes’ unspecifically. In various parts of Ireland, those
have been burnt and the ashes put to service: as a cure for ringworm in
Offaly^20 and Waterford^21 or, mixed with lard and made into an ointment
applied to ‘wildfire’—presumably shingles—in Westmeath,^22 or to the pus-
tules of chickenpox, to prevent scarring, in some other, unidentified area.^23
The sole British record traced of a medical use of ‘rushes’ is as a wart cure
in Cheshire.^24
Cyperaceae
Eriophorum angustifolium Honckeney
cottongrass
northern and central Europe, Siberia, North America
(Name confusion) The misattribution to Eriophorum angustifolium of the
Irish Gaelic name for self-heal (Prunella vulgaris) has led to erroneous records
of its use in Wicklow^25 and, probably from the same cause, in the Aran
Islands, too.^26
322 Lemna minor