From their literature: "Unfortunately modern cemeteries all too often destroy natural landscapes and chew up valuable open space: creating fertilized and herbicided, environments with dense interments and plastic flowers. A tremendous amount of money goes into expensive “leak-proof” caskets, vaults and mausoleum crypts, and to “perpetual care”.
Their solution: Burials and ashes scatterings occur in these parks, but the interments must be natural, “dust to dust” burials: ... no toxic embalming fluids, no vaults, and only biodegradable caskets.
The cemetery is basically a forest "fertilized" by the bodies and ashes. The only thing they don't do is grow plants designed to be edible, as far as I can tell, for cultural/religious reasons I gather.
They have different burial packages: The Bokashi, which guarantees that you'll be fully returned to the soil in 3 years; The Carp Diem, which uses water hyacinths, cattails, and koi to make you available to every step of the food chain, as part of a Japanese garden-like theme of harmony and balance; and for those on a budget The Forest Finish, which will leave your body in a primeval forest for the scavengers.
And for those who prefer a simple cremation, through 2010 they will even cover the carbon offsett credits for no extra fee!