Those of you who know the familiar flower yarrow might well think that that is what this is, but it's not. It sneezewort (Achillea ptarmica); an Achillea like yarrow but a smaller plant with less feathery leaves.
July and August, riversides and wet meadows are good places to look for flowers a bit out of the ordinary and that is where you find sneezewort. It is described as being 'local' and so where it occurs it is usually quite common but finding places where it occurs is a bit more difficult. Certainly, the lower reaches of the River Frome is one place. It has a preference for acid soil rather than chalk so it is unlikely to be found further up stream in the chalk areas where our streams tend to originate.
I have no idea why it is called sneezewort but I suspect it has connections to the Great Plague of 1665! It has a number of other common names too. The leaves can be cooked and eaten and they are also used to extract an essential oil used in herbal medicine. The leaves can be used as an insect repellent, quite a versatile plant!Sneezewort: bless you bless you all fall down