Possible fungal infection to a 10 - 15 yr old Blue Spruce

Asked February 17, 2020, 2:24 PM EST

We have a 12 - 15 ft. blue spruce, possibly a FAT ALBERT variety. It had been thick and growing nicely till about a year ago and I noticed that it is thinning.. There are also some limbs that appear to be dead. On checking with your website, I found 2 possible fungal diseases: Needle cast: Rhizospaeria or Cytospora canker. Leucostoma kunzei What might be a possible treatment and where could I locate it?

Baltimore County Maryland

1 Response

Here is some information. This past season we have received many questions on decline of blue spruce. In general, they are not really well suited for our area as they are native to climates further to the north. Blue spruce are susceptible to fungal diseases when stressed due to poor site conditions, drought, etc. such as
Cytospora canker http://extension.umd.edu/hgic/cytospora-canker-spruce
and Rhizosphaeria needlecast. http://extension.umd.edu/hgic/evergreen-needle-cast-diseases-trees-and-shrubs

For the above diseases all you can do is prune bare branches during dry weather and keep the trees well watered during dry periods. No fungicides are recommended. Also, here is our blog post on blue spruce https://marylandgrows.umd.edu/2018/01/08/whats-wrong-with-my-blue-spruce-tree/

You can submit photos of the whole tree, around the base, and affected branches so we can see what you may be dealing with.

Marian