Common bracken is a herbaceous perennial plant, deciduous in winter. The large, roughly triangular fronds are produced singly, arising upwards from an underground rhizome, and grow to 0.3–1 m (1–3ft) tall the main stem, or stipe, is up to 1 cm (0.4 in) diameter at the base. It dies back to ground level in autumn. However, ptaquiloside is water soluble, and is reduced by soaking bracken in cool water. It also degenerates at room temperature, which explains why the rat studies were done with the toxin stored at −20 °C (−4 °F). At boiling temperature, carcinogen denatures almost completely. Salt and baking soda also help with volatilizing the chemical. Further discussions on the nature of different fern species and their toxicity can be found under. Learn more about Bracken