Guest Post by Laura Cooper

Manihot esculenta leaf sewn onto this Herbarium sheet.

I remember hearing as a small child the rumour that swallowing a single apple seed would kill you. Whilst I later learnt that this was false, it is true that the cyanide in apple seeds means that theoretically, chewing a large number could cause poisoning.

Cyanide is a simple chemical produced by many organisms, often as an unwanted by-product. But cyanide is found in relatively high levels in many plant species, including the seeds of many common food plants, such as peaches, almonds, and legumes.

Manihot esculenta tubers, sold as cassava or yuca. Source.

The cyanogenic plant I will focus on here is cassava, Manihot esculenta, also known as yucca. It’s tubers are a major carbohydrate source throughout the tropics due to its drought tolerance and ability to thrive in poor soil. It is probably most…