Donegan's Tree Service - Leesburg, Loudoun Country, Marshall, and The Plains, Virginia
ISA Certified Arborist, Tree Care, Landscaping, Pest Management


Advice for tree owners everywhere

The Blue Spruce Fungus Among Us


There’s a fungus among us — again — and it’s spreading across the East Coast. I started noticing this in 2016 on my own Blue Spruce Trees. Every year for Christmas when my children where young we would purchase a live Christmas tree. We started the tradition in 1990 and would plant them on our own property.

Now these majestic Blue Spruce have grown to a height of 30’ and their placement provides a screen from the traffic on Evergreen Mills Road. I am heart broken that I didn’t see it sooner in my own trees.

I first suspected it was spider mites and treated for that with a mite spray. With my busy schedule taking care of everyone else’s trees, I didn’t check back on my own to make sure that the treatment had been effective.

This fall as things wind down, I’ve had a bit more time to focus on my own trees again and I am hopeful that it isn’t too late for them. Unfortunately the problem isn’t just with my trees, I started noticing throughout the county that large Spruce trees are in decline at the bottom with the problem working its way up the tree. After more research, I discovered that these trees are infected with a fungus called Rhizosphaera kalkhoffii.

During the winter months, the fungi stays in the needles, but in the spring, the infected needles will release spores during wet weather, infecting new growth and causing the cycle to repeat itself. This will continue for a few years until the bottom of the tree gets thinned out and begins to die back.

The reason it starts at the bottom instead of the top of the tree is that the base stays wet longer allowing the fungus to work it’s way up the trunk. This causes the tree to go through the winter in a weakened state, resulting in further decline and, eventually, death.

For my own Spruce trees, I am cutting off all the dead and dying limbs at the bottom, giving them fertilizer and starting a fungicide treatment in March. Hopefully it won’t be too late to save these beautiful trees. If you suspect your trees may be dealing with the same challenge, contact us for an inspection.

Jim Donegan