It's a tough world out there in our Woods.

A fungus growing on a fungus, growing on a fungus.

The white mildew is probably a parasitic fungus called the Bolete Eater (Hypomyces chrysospermus), which itself is growing on a fungus commonly known as the Parasitic Bolete (Pseudoboletus parasiticus). This in itself is growing on a Common Earthball, (Scleroderma citrinum), which has sent out coarse mycelial threads into the surrounding earth to feed itself and all the hangers on.