Phacelia tanacetifolia Benth., Phacelia

Introduction, neophyte, a very rare casual, either a garden escape or from wild bird seed mixture.

23 June 2003; Northridge, R.H.; south corner of Holme Bay, Lower Lough Erne.

This attractive pale-blue-flowered N American member of the Waterleaf family has been found only twice in Fermanagh, in a heap of discarded garden gravel on the lakeshore, as detailed above, and secondly (again found by RHN, 24 August 2004) on a roadside bank near the Spence farm at Moyglass, 5 km NW of Enniskillen. The plant, which is an annual, has distinctive dissected, Tansy-like leaves. It is a rare casual alien introduced in seed mixtures either for feeding wild birds or pheasants, or for growing so-called 'wild flower meadows'. It may also be deliberately grown as an ornamental garden annual, or as a 'green manure' in allotments, or in arable fields as a nectar source to attract bees and hoverflies that prey on aphid pests. P. tanacetifolia may also appear as a seed contaminant in re-seeded lawns and other grasslands (Clement & Foster 1994; New Atlas; Cat Alien Pl Ir). The plant is found typically in cultivated or disturbed ground, often where waste is discarded. It is generally regarded as a casual and most populations are not expected to persist.

P. tanacetifolia was first cultivated in Britain in 1832, but was not found there in the wild until 1885. In Ireland, the first discovery was in a field near Downpatrick, Co Down (H38) in 1962 (H.J. Killick, in: Preston et al. 2002; Cat Alien Pl Ir). The recent history of its occurrence suggests it has increased quite considerably in Britain. There may also be a much less obvious increase in Ireland. The Cat Alien Pl Ir details finds in a total of six Irish VCs prior to our 2003 Fermanagh record, but only one of these is featured in the New Atlas hectad map.