Thank you for taking the time to tell me about puffballs. It is reassuring to know that the spores are not harmful.

Puffballs, probably, although there are others that release spores when the mushroom is ready. Earth stars are another. Look them up. When it rains, raindrops hit the dried papery central globe (the endoperidium), and that pressure is just enough the'puff' the spores, like a dust, out of the hole in the middle, up into the air. Fantastic nature. Phil J

The mushrooms are a type of Puffball, Iam, but I don't know which sort. The dust is the spores of the puffball being broadcast into the air. If they are harmfull - I don't really know but would suspect not unless you were breathing them in regularly when you might get pneumonicosis, such as miners used to be susceptible to.

Thank you Philjeffs and Bulbaholic for taking the time to answer my question. It is reassuring to learn that the dispersed spores are not harmful. Iam

Hi Iam, it's worth bearing in mind that, particularly at this time of the year, the air is teeming with fungal spores riding their way around to find new homes, and we're all breathing them in all the time. Although some people do exhibit some respiratory sensitivity to them they are nowhere near as troublesome as plant pollens in that respect.

Puffballs are edible when young incidentally!