Hi, we installed a number of microbiota decussata (Russian Cypress) shrubs on a sunny, well-drained slope. The shrubs did well for the first two years, but this year, (3) are clearly dying. They start looking weak in color, and then fade to a light brown, losing all their green. There is no condition leading to root rot, nor are there clay soils. I was the landscaper for installation, and the slope is built from a decent loam (no standing water). There are (3) other microbiota nearby on the same slope that look fine. I have searched online for diseases and insects that may cause the problem to no avail. Do we replace them, or switch to other stock? Many thanks.
