By Dorey
Canada 
I have white oval spots under the leaves and on the stems of the Pieris japonica
22 May, 2021
By Dorey
Canada
I have white oval spots under the leaves and on the stems of the Pieris japonica
22 May, 2021
Welcome to GoY
Are they raised spots? if yes sounds like scale insects.
Have a look at this site.
https://www.rhs.org.uk/Advice/Profile?pID=224&cID=1597
22 May, 2021