Cherry Laurel disease identification

3 of my mature, established cherry laurels have died and more plants seem to be going that way. Any help in identifying the cause and providing a fix is appreciated. I am not sure if its fungal or another type of problem.

There appears to be a lot of scale insects infesting this/these plants. Can you take some additional images of stems/branches, such as closeups of the parts in the fifth image above?

Scale are piercing/sucking insects that can weaken plants, but unless there are overwhelming numbers they don't usually kill mature established plants.

You should also provide images of the whole plant and some idea of the context in which these plants are growing.

That second and fourth picture look like phytophthora, which is a fungal infection (best known as root rot) that can attack any plant but in my experience, it attacks more easily when the plant has been stressed by another factor such as insects, heat, or water (over/under).

My cherry laurels suffer from the same diseases and scale, have been on life support for years, and I recently decided to give up and replace them. The 3rd photo shows shothole fungus; see http://pnwhandbooks.org/plantdisease/prunus-laurocerasus-leaf-spots-and-shothole.

Mine have some shothole fungus, but that isn't as bad as whatever disease causes the leaves to turn yellow and die, because new leaves never grow on the new branches. I have been spraying them with an organic copper-based fungicide, which does help. I refuse to use systemic toxic substances on a berry-producing shrub because I do not want to poison the birds.

I've concluded that excessive humidity is the primary problem, because the worst areas face a fence and thus have marginally less air ventilation. In short, these might not be the best shrubs to grow in VIenna, Virginia or Towson, MD due to our extremely humid summers.

Oops, I just saw that the link doesn't work. Anyway, shothole fungus is definitely the cause of the holes in pic # 3. I just did some more reading online and found out that prunus laurocerasus are more prone to diseases when crowded together, which might explain why mature laurels are more likely to be plagued by disease. I have 4 shrubs that are growing into each other, but like I said above, the worst damage is on the fence side. That side gets a little more sun, so I do think the reduced air circulation is the main problem. Just like roses, they might just not be easy to grow in our area due to the humidity.

Thanks to all who replied. I had a local professional come by and take a look and he believes it is a large infestation of white prunicola scale. He recommended cutting away dead branches and treating aggressively with oil in the spring. Now I just have to decide if its worth trying to save the last laurels or remove and put in new ones. Does anyone know if the scale will affect new plants if I remove the old plants and soil?

I think that once the scale is dead, it's dead, unlike the more serious diseases that plague cherry laurels. In my experience, new growth from the trunks, woody branches and around the bases of cherry laurels is non-existent to minimal. Mine are in part sun; perhaps there would be more re-growth in full sun conditions, but my vote would still be for replacing them.