The Maidenhair Tree (Ginkgo biloba) is sometimes described as a "living fossil". As I said in an entry last December: "All other plants in the world are members of groupings of related plants but Ginkgo has a unique taxonomy being the only member of its division, class, genus, order and family of which it is the only species. In prehistory there were other Ginkgos but they are gone. The Maidenhair Tree was here with the dinosaurs (and probably eaten by them)."
 There is a large one at the South London Botanical Institute which has shed its golden leaves and I passed an hour or so last week sweeping them off the tarmac driveway and carting them onto the compost heap. I made the point in my last entry that leaves are best in their own pile to make leafmould (by fungal action) and in fact a mass of leaves is likely to overwhelm the bacterial action of a regular compost heap.
 However, one of the gardeners at the SLBI gave me a good tip regarding Ginkgo (thanks Cath). She noted that Ginkgo leaves break down much quicker than other leaves so are ok in general composting. Most trees have net-like patterns of veins in their leaves but Ginkgo has leaves with parallel veins- presumably a characteristic of its ancient origins. These "primitive" leaves decompose more rapidly.