Question
i lost a holly bush last year to some kind of disease/insect that  
produces brown spots on the leaves and then the leave evenually
turns all brown and shivels up.  I sprayed the bush with and
insecticide last fall and it seemed to help but then the disease
came back and I was unable to spray it again because I was
pregnant. The other day,  I noticed that the disease is now on my other
holly bushes and looks to be possibly spreading to some of my
other bushes. I am afraid that I am going to lose all of my
landscapoing to this problem. What can I buy at the local
hardware store to spray and rid them of this disease? Also,
where is it coming from? Could it be coming from the mulch I
am putting down? I buy the high end red mulch from a local
dealer.

Please help. Thanks!!

Answer
Christina,
From what you have described, it sounds like the hollies are bring attacked by holly leafminer. This fly larvae tunels around inside the leaves of american hollies and causes them to brown out and die. In order to control this insect, you need to spray it with a systemic insecticide, such as Orthene, which the larvae will injest and die.
The adult leafminers are actually tiny flies that can travel up to 1/2 a mile from where they hatched.
This type of leafminer only attacks hollies, so if you are noticing damage on other types of plants, then there are other conditions that need addressing. Is the landscape less than 5 years old? If so, then it could be going into transplant shock. Does the area drain well or does it retain water? Too much water will drown out the roots, eventually leading to the plants death.
In any case I would recommend treating the hollies for leafminer and fertilizing all of the plants this spring to help strengthen them.
Ed Gulliksen