Help! Bushes & trees dying of mold (?)

A few weeks ago, I noticed one of the bushes in front of my office had this white mold on the leaves. I was concerned and brought it to the boss's attention, but he said 'it's nothing' and dismissed it immediately. Meanwhile, this mold-looking stuff has spread to the trees and bushes on either side of the original infected bush. This mold seems to be very fast spreading and is covering most of the plant, with some of the leaves now entirely white. I don't even know what the plants ARE, let alone what this mold is. Wikipedia wasn't a huge help- it would seem to be either "white mold" or "powdery mildew". I just don't want our plants to die! Can anyone tell me what this plant disease is and how to cure it? Is there some kind of all-in-one plant aid I can use to help our plants recover?

It looks like powdery mildew to me also, what the cure is a spray from the garden center, but to prevent it coming back or helping to reduce the area you already have is to improve the growing conditions, the plants either have no good air circulating the foliage and the soil is too dry, these conditions are common more on plants growing close to walls where there is no air at the roots and being close to the wall also means the soil dries out too fast even when there is water added, so if the boss really cant be bothered to do anything, you are going to have to either watch the plants get sicker, or try fix them yourself, to start with I would nip off all the infected leaves as the slight breeze can spread the mildew, also insects and bird spread it as they visit the tree, use gloves to do this and burn or get rid off all the leaves, a mulch at the roots might also help retain some moisture in the soil. by the way, this fungus can stay dormant in the soil and attack again, so really get rid of all infected foliage as you find it. Good luck. WeeNel.

Looks like some sort of Euonymous plants you have there. Many of them are very prone to getting powdery mildew, especially when you have damp nights and no air movement.

If you don't want to spend the money on a store bought spray, here is a recipe for making your own:

To make ONE GALLON of spray, mix the following into ONE CUP of water:
1 1/2 tbs. baking soda
1 tbs. Canola oil
1tbs. of INSECTICIDAL SOAP

THEN, add 1 tbs. of White Vinegar to the mix. You HAVE to add this LAST...otherwise it will foam all over everything.

STIR the mix and add enough water to make ONE GALLON of water.

If you can get your hands on a pump sprayer, that would be the best thing to apply it with. (Providing it hasn't been used for weed killer).

DO NOT spray if the temps. are expected to be over 85* F.
It works best to do it on a coolish day and do it in the morning.
Thoroughly douse the plant, getting all the foliage wet.

This really works wonders. The mildew will virtually disappear before your eyes, as the spray "neutralizes" the mildew.

IF you can't get a tank pump sprayer, you can use a hose-end sprayer.
Pour the mixture into the container, then add just enough water to bring it to the ONE GALLON mark on the cannister. (You won't need to add very much.) Then turn the water on and spray until the contents of the cannister are gone.

This works really well for roses, too.