American skunk cabbage
L. americanus is a tall herb (up to 1.5 m high, covering approximately 1 m2 ground) with large (40-70 cm up to 1.5 m) glossy light green leaves coming from short thick fleshy rhizomes (up to 30 cm long and 2.5-5 cm diameter). The 1 to 2 (sometimes up to 4) inflorescences are surrounded by a showy bright yellow spathe up to 45 cm high, enclosing one fleshy, up to 25 cm long spadix carrying many flowers at the bottom. Flowers are small, yellowish green, often monoecious with female flowers below and male above (with generally 4, sometimes 6 stamens); bisexual flowers are also found. Flowers consist of generally 4, sometimes 6 free or fused sepals. They usually flower between March and May before leaves appear (variable dependant on location in Ireland). The fruits are green berries at the end of the spadix, and mature in its natural range from June to early August (also variable regionally). Flowering and fruiting are earlier in the native range as compared to northern and central Europe (Alberternst and Nawrath, 2002). As it is one of the species on the EU Species of Union Concern first list of 37 species, the UK, Ireland and EU have produced Risk Assessments (R.As.).