Possible needle cast?

Asked May 12, 2020, 1:20 PM EDT

I have 3- black hills spruce trees roughly 7-8’ in height. They are starting to shed needles making them look thin especially lower and inner part of tree. They are getting new growth but I’m afraid that without proper treatment they will die. I’m sending some images hoping you can help me determine the problem and possibly my best treatment plan. Thank you Lance Challender

Jackson County Michigan

1 Response

The symptoms do suggest needlecast. I cannot see for sure in these pictures but needles should normally have rows of whitish dots. These are the stoma or pores of the needles that allow gas exchange. In needles turning yellow you should see that these white pores are filled with black growth, which is a sign of needlecast. Also the dropping of older needles from the inside, near the bottom of the tree is a symptom of the disease. Needle drop also occurs commonly on crowded trees that shade each other too much. Fungicides can be used to protect this years new growth. This is done in a couple sprayings starting when new needles are half grown and then following label directions on a second spraying. See the following article on needlecast: https://extension.umn.edu/plant-diseases/rhizosphaera-needle-cast