Meanwhile during some Tree surgery in Cannock...
It happens in these conditions:
1. In large concentrations of cherry laurel, like in a hedge or laurel woodland (it sometimes happens on portuguese laurel too).
2. When the weather is generally damp, with low amounts of sunlight.
3. When there is more sunlight & dry air, fresh growth will replace “shot” leaves and the issue should not return (until the humid weather does!)
Organic Prevention of Laurel Shot Hole:
1. Sweep up fallen Laurel leaves regularly.
2. Prune out dead or ingrowing branches inside the plants.
3. Look for ways to improve the air circulation around the plants: sometimes a piece of nearby fence can be removed, or other plants cut back.