Blue Spruce Die Back
I am having a problem with two of my Douglas Blue Spruces in my yard. One is far worse than the other. They both are experiencing considerable die back on the inside of the tree and seem to be getting worse each year. The tips are very lush and green but behind the tips there are no needles, just branches. The needles have never turned brown to my knowledge, they just are no longer there. I have seen this issue on lots of Blue Spruces around Baltimore County and it seems to be an almost universal problem around Baltimore County (although some trees do not appear affected). I have also attached a picture of the front yard tree in 2013 and 2017 to show its decline. The one in my front yard is a magnificent tree and I would hate to lose it. Both trees are likely
Here is some information. Blue spruce can be susceptible to Cytospora canker and Rhizosphaeria needlecast, fungal diseases. All you can do is keep the trees well watered during dry periods, make sure mulch is not thicker than several inches and away from the trunk, and Prune plant material during dry weather. No chemical control is recommended.
Blue spruce, in general, are not really well suited for our area as they are native to climates further to the north. Cytospora canker occurs on trees stressed by drought or other site conditions. http://extension.umd.edu/hgic/cytospora-canker-spruce
Rhizosphaeria needle cast disease. The infection period is long - spring through midsummer. The needles are affected in the fall and needle drop occurs in the spring. Pruning out severely infected branches is the best control method on branches that show sparse growth. Spraying large trees with fungicides can be complicated - getting good coverage, timing, etc. and not recommended. For more information see the link on our website http://extension.umd.edu/hgic/evergreen-needle-cast-diseases-trees-and-shrubs
For an onsite diagnosis regarding the health of your trees contact several certified arborists for the best way to proceed http://www.treesaregood.org/
Thank you for this great information. I believe that my trees are suffering from the Cytospora canker.
It is sad to see that there is nothing I can to prevent other than water them during drought. I will take steps to prune aggressively in the fall and have a nice bonfire.