Posted: 08/08/2014 at 17:37
I've seen that Wikipedia states they grow to 20m but I'd take that info with a large pinch of salt.
Everywhere else I've seen White Mulberry described as a small to medium sized tree and this site says it'll grow to 5-10m http://www.barcham.co.uk/trees-for-sale/buy-white-mulberry-morus-alba-platanifolia
If it was me I'd want to be much more sure of my information before I started reducing the size of what appear to be lovely well-balanced trees, and possibly ruining their overall appearance.
I think more research is needed.