Hello Annette,
Pieris can be propagated by cuttings in Spring. Usually you wait for the young red foliage to turn green before taking cuttings but time is of the essence here because the plant is damaged and there is no time to wait to take cuttings.
If you can, take several cuttings of semi ripe, green wood shoots from the
plant. i.e. it must not be the uppermost, softest shoots and it must not be
the woodiest that is found as you work your way down the plant.
The cuttings should be 6-8cm long. Keep 5 or 6 leaves on each cutting and actually cut the largest leaves on each cutting in half to reduce surface area and therefore water evaporation.
When taking the cutting from the plant, cut below a leaf joint (node) as
there is is more hormonal activity there which improves your chances of
successful rooting. Dip in hormone rooting powder.
Pot up the cuttings in specialist cuttings compost, cover with a clear
polythene bag (to reduce moisture loss) and if possible have about 60F of
basal heat e.g. stand on top of a domestic boiler.
Don't worry if the leaves die off, you are looking for new growth from the
leaf buds on the stems. Rooting could take 2 months.