Sir – Judging by the picture accompanying last week’s article article in which fears were raised about giant hogweed, the plant concerned is hogweed, Heracleum sphondylium which is not a cause for concern.

It is giant hogweed Heracleum montegazzianum which is much larger with flowering umbels up to three feet across that is the problem, causing sensitisation of the skin to ultra violet light.

Fred Topliffe
Oxford