Swiss Needle Cast

Asked April 14, 2014, 10:43 AM EDT

I have approximately 15,000 Douglas Fir trees on my 250 acre property. The majority of these trees were planted almost 30 years ago. I also have approximately 1000 fir trees that were planted within the last 3 years. All of the newer plantings seem to be severely infected with the Swiss needle cast. I am also seeing it spread to the older trees as well. I have read up on the spraying techniques but I do not know if I need to hire someone to spray or if I can do it myself. The larger trees would need to be sprayed from the air but I could handle the smaller plantings from the ground. Any information would be helpful. thanks you.

Lycoming County Pennsylvania

1 Response

The first step is to properly identify the problem. You can submit a sample to the Penn State Plant Disease Clinic (see

If the problem definitely is Swiss Needle Cast, here is a good web-based resource we found from Oregon State University, College of Forestry, Swiss Needle Cast Cooperative:
Also, check the Identification and Images page at
And the Forest Health Fact Sheets at

If you have further questions about Douglas Fir Trees, you may want to contact Tim Abbey, a Penn State extension educator from York county. He can be contacted at or by calling 717-840-7408. Also, Dr. Donald Davis, a Penn State forest tree pathologist, can be contacted at or at 814-865-1689.

If you decide that pesticides need to be used, this is what must be considered. You can apply general use pesticides on your own property. (General use pesticides are those that anyone can purchase.) However, if you need to apply restricted use pesticides (pesticides that require a pesticide applicator certification to purchase), you have two options. Either you can hire a certified pesticide applicator (in Category 01: Agronomic Crops or, if needed, Category 25: Aerial Application) to do it OR you will need to acquire a Private Applicator Pesticide Applicator Certification. This requires passing an open book exam on (focusing on general pesticide safety) and paying a fee. You can purchase study materials for the exam, see To find examination dates and locations, go to

For more information about the certification process, please see our Pennsylvania Pesticide Applicator Certification brochure at (or

I hope this helps to answer your questions.