My Japanese boxwood are turning a yellow to dark brown color on the leaves. What is the problem?[/img][/list]

The problem is Japanese Boxwood. This plant is suseptiple to nematodes, leaf miners, scale, soil fungus and freeze damage. How many do you have and how much do you like them? You can pull them out and replace with dwarf yaupon holly. This is the dwarf version of the native Texas Yaupon Holly tree which has none of these problems, requires less water, looks great all the time (including winter) and will last for years.
Tony M