Douglas fir getting bare

Asked November 19, 2017, 1:43 PM EST

I planted a Douglas fir (fairly certain that's the type of tree) ten plus years ago and the tree has lost many needles. I'd appreciate input on how to revive the tree. The tree is on a street named Chinaberry - it's clearly not a Chinaberry tree!

Frederick County Maryland disease issues blue spruce cytospora canker tree rhizosphaeria needlecast

1 Response

The tree looks like a Blue spruce and is susceptible to fungal diseases such as
Cytospora canker and Rhizosphaeria needlecast. 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. There is not much you can do other than water during dry periods. Make sure mulch is no thicker than several inches and keep away from the base of the trunk. Prune dead plant material during dry weather. 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

mh