Powdery mildew on lilac
I know this is technically a shrub, but I thought I'd ask here anyway since it's tree size.
The lilac shrub is original to our home. It's planting location is not the best, right next to the house and windows, but I've trimmed it up to tree form to allow for better air circulation, and have been on a three year pruning schedule to remove all the older, crossing branches. It's on a west facing wall, full sun noon on.
Given the location, with windows in close proximity, an air conditioning unit within three feet, it's not the easiest to treat with any type sprayer that attaches to the garden hose. I was perusing my options yesterday, not sure what to get.
I have the 3 in 1 Bayer systemic for roses, but not sure if this would be adequate for a shrub this size (reaches my second floor airing porch).
What is the best product to treat powdery mildew on large shrubs like this, that won't harm the birds?