Silver Maple Or Red Maple?

The gardener's often get asked questions by visitors about the names of plants in the gardens, most of which are answered, but today one was asked which they were unable to give the answer to. The question, the name of a tree with tiny clusters of red/yellow flowers on the branches? This question needed further investigation. A large tree with the flowers very high up but a few were found on the ground. Leaves were also found around the base of the tree giving the Genus in which to look, Maple (Acer), now which species is it? Next to the book 'Trees of North America and Europe' by Roger Phillips and Martyn Rix, full of photographs to refer to, Silver Maple (Acer saccharinum) or Red Maple (Acer rubrum). The question has almost been answered but which of the two Maples is it? The team are still undecided, it may even mean waiting until it is in full leaf and even as far as waiting for the autumn colour. In the mean time they are waiting for the flowers to open completely in the hope that this will give them the answer sooner rather than later.