Wood For Birds Nests/Boxes (Hengistbury Head BH6)

Old pieces of 1930s skirting boards.
Have kept for years for husband to make birds nests/boxes for me, but it's not going to happen.
Will need to be cleaned as have been stored outside in a plastic bag.
Still good solid wood, 40 to 50cm long x 17cm wide x 2.5cm thick