Knowledgebase
dwarf blue spruce plants #799039
Asked July 01, 2022, 4:20 PM EDT
Hello,
I've noticed that some of the needles in many of my St. Mary's broom dwarfs have become dry and lost color. This has happened in the past, in which case I've trimmed the affected branches. This spring and summer, however, the situation is affecting more plants more extensively. Can you tell me if there is a treatment?
Many thanks!
Montgomery County Maryland
Expert Response
Hi!
We think your spruce may have a disease caused by a fungus called Rhizosphaera needle cast. Check out this page, which goes into detail about how to identify the fruiting bodies on the needles. The damage usually starts low on the tree/shrub and then moves up. Your pruning in prior years was effective in managing Rhizosphaera and we recommend continuing. You can have a certified arborist come out and treat the remaining (nonaffected) foliage with a fungicide to prevent the spread.
Jamie
