and be careful: puffballs are harmless, but some other mushrooms, like the death cap mushroom, can resemble a puffball in their early stages. from another site:
Landcare Research mycologist (mushroom expert) Peter Johnston said when the death cap was young it was easily confused with a puffball, which some people ate.
"Very difficult to tell them apart... you have got to know what you are eating," he said.
Toxins in death caps stop human cell division, meaning organs which form new cells, such as the liver, stop working, Dr Johnston said.