Poisons, Sweet Scents and Parasites

Common ragwort (Senecio jacobaea) or Buachalán buí in Irish is blooming now. (1)  This poisonous plant is common on grasslands, wastelands, roadsides and arable land.  It is a member of the daisy family with yellow disc florets in the centre and ray florets circling the disc florets

Ragwort (1)
Red tailed bumblebee on ragwort (2)

It is classified as a noxious weed because of its potential to poison livestock.  It is, however, the food plant of the caterpillars of the poisonous Cinnabar moth and attracts many insects(2) This day-flying moth displays red and black warning colours and is easily recognisable. The moth’s caterpillars absorb the toxins in the plant and so are mostly avoided by predators.  Their conspicuous black and yellow bodies (more warning colours in nature) remind one of the Kilkenny colours, black and amber. (3)

Cinnabar moth caterpillars (3)
Lady’s bedstraw (4)

Despite its poisonous properties it was used for curing many ailments such as coughs and sores.

Lady’s bedstraw (Galium verum) or Boladh cnis in Irish is common on roadsides, grasslands and sandy places. (4)  The narrow leaves are in whorls of eight to twelve on the square stem.  The four petalled flowers smell sweetly and were used as a strewing herb on floors and to freshen up bed linen.  When the flowers wilt, they emit a particularly sweet scent which has been compared to that of new mown hay.

Yellow rattle (Rhinanthus minor) or Gliográn in Irish was once common in meadows and pastures. (5) Nowadays, it is only occasionally found in neglected grassland or in modern, newly planted wildflower meadows.  It is a useful plant in these because it is a parasite of grasses and keeps them in check so that the wildflowers thrive.  Bumblebees are its main pollinators.

Yellow rattle (5)