The world turned upside down

Most people's roots grow in a downwardly direction as ane fule kno. Delightful phenomenon of the week is the upwards-growing or negatively gravitrophic rootlet that grows out of the nodules that our good friend Myrica gale (bog myrtle) makes on its roots in collaboration with mutual friends Frankia bacteria.

This happens when the oxygen concentration in the soil is very low, which is often for the Myrica gale, which likes to live in stagnant bogs. Frankia like a bit of oxygen for their business purposes and so they make the lobes of lots of the nodules send rootlets up to the surface, like snorkels. Marvellous.