The line between whether a plant is a "tree" or a "shrub" is sometimes very thin and quite blurry! We use the following criteria to decide which type applies to a certain plant:
Cedrus deodara 'Feelin Blue'
Cryptomeria japonica 'Golden Promise'
Hydrangea luteovenosa 'Aureovariegata'
Ilex crenata 'Piccolo', Dwarf Japanese Holly