Thanks for contacting CSU Extension. I suggest following up with the Delta master gardeners. They are in the office Wednesdays from 9:00-10:00am. 

It would be helpful if you could bring in a sample from your tree (small branch with leaves showing the spots.)  I'd recommend dropping off the sample, either Monday or Tuesday, in which case, they'd follow up by phone. Or bring in a sample at 9am on Wednesday and chat with them in person. 

The Delta office is located at 525 Dodge Street, Delta and is open 7:30-11:30 and 12:30-4:30,<personal data hidden>.