I guess if I'm going to get any cutting wood of Balfour's Willow ( Salix x balfourii ) now is the time!
I've tried The National Willow Collection @ Rothamsted, with no response.
I've also discovered that some people grow Basford Golden Willow (Basfordiana) as S x balfourii, whereas other people think it is S x fragilis... so that muddies the water somewhat!
Tim DH