I had to change my path through the Adelaide Botanic Garden to avoid these falling fruit. Photo taken around the middle of May. Genus and species please.
Signs like that are usually put up for Bunya Araucaria bidwillii, but the green items on the ground don't look right for that. How about Maclura pomifera?
Yes it's Maclura pomifera. The fruit has been posted on the forums so many times, I didn't think it would be too difficult for this group. Part of the stumper here was the fact that it is an exotic fruit in Adelaide.