zimmerman pine moth and emerald ash borers - Ask Extension
Hi, I have about 40 blue spruce and Austrian pines on my lot. I have noticed what you describe as zimmerman pine moth on one of my Austrian pine and...
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zimmerman pine moth and emerald ash borers #199934
Asked July 16, 2014, 10:07 PM EDT
Hi, I have about 40 blue spruce and Austrian pines on my lot. I have noticed what you describe as zimmerman pine moth on one of my Austrian pine and am worried about it and the other trees I have. What can I spray to stop the advancement on this tree as it appears limbs are turning brown and dying. I also worry about the spread to others. I also have 8 or so ash trees that I have been applying baer brand solution to and have still lost three trees to what I assume is the emerald ash beetle. I could use some good advice as to a more aggressive approach to killing these bugs. I love my trees and am losing some. If you could recommend some treatments or someone that could help me with my problem, I sure would appreciate it. Thank you, Steve Pendleton
Larimer County Colorado
Expert Response
Hi Steve,
Zimmerman pine moth can be damaging to pine trees, and control may be necessary. However, products should be applied in early spring (late April/May) to the trunk. Please refer to the CSU Fact Sheet on this subject: http://www.ext.colostate.edu/pubs/insect/05591.html
It's unlikely that your ash trees have emerald ash borer, as it's yet to be confirmed in Larimer County. This insect has only been found in the Boulder area. However, we do have lilac-ash borer, which is a very common insect of ash trees and probably the #1 insect we see on ash currently. The product you used will NOT control lilac-ash borer. Because lilac-ash borer is a clearwing moth, the active ingredient in the Bayer product, imidacloprid, is ineffective on moths. Instead you must use trunk sprays containing permethrin or bifenthrin.
The best prevention of lilac-ash borer is to have a healthy tree...reduce stress, water regularly, make proper pruning cuts and avoid damage to the bark. Preventative sprays will prevent new attacks, but will not cure any damage currently done. Lilac-ash borer make large, round exit holes in the trunk. which you can see at eye level (1/4 to 1/2" in diameter). Please refer to this Fact Sheet for more information: http://www.ext.colostate.edu/pubs/insect/05614.html
Emerald ash borer create small, D-shaped exit holes, generally attack the upper canopy of trees first. The holes are 1/8" in size. For the latest information on emerald ash borer (including current citings), please go to www.eabcolorado.com Treatment for emerald ash borer is not recommended in Larimer County at this time.
Zimmerman pine moth can be damaging to pine trees, and control may be necessary. However, products should be applied in early spring (late April/May) to the trunk. Please refer to the CSU Fact Sheet on this subject: http://www.ext.colostate.edu/pubs/insect/05591.html
It's unlikely that your ash trees have emerald ash borer, as it's yet to be confirmed in Larimer County. This insect has only been found in the Boulder area. However, we do have lilac-ash borer, which is a very common insect of ash trees and probably the #1 insect we see on ash currently. The product you used will NOT control lilac-ash borer. Because lilac-ash borer is a clearwing moth, the active ingredient in the Bayer product, imidacloprid, is ineffective on moths. Instead you must use trunk sprays containing permethrin or bifenthrin.
The best prevention of lilac-ash borer is to have a healthy tree...reduce stress, water regularly, make proper pruning cuts and avoid damage to the bark. Preventative sprays will prevent new attacks, but will not cure any damage currently done. Lilac-ash borer make large, round exit holes in the trunk. which you can see at eye level (1/4 to 1/2" in diameter). Please refer to this Fact Sheet for more information: http://www.ext.colostate.edu/pubs/insect/05614.html
Emerald ash borer create small, D-shaped exit holes, generally attack the upper canopy of trees first. The holes are 1/8" in size. For the latest information on emerald ash borer (including current citings), please go to www.eabcolorado.com Treatment for emerald ash borer is not recommended in Larimer County at this time.
