Insect treatments - Ask Extension
This Spring I will be removing, and probably burning this tree and any other Jack Pine that appear to be infected the gall.
Also, I would like to ...
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Insect treatments #892301
Asked February 04, 2025, 4:11 PM EST
This Spring I will be removing, and probably burning this tree and any other Jack Pine that appear to be infected the gall.
Also, I would like to follow-up on some previous questions that I have had.
To summarize, I have White Pine Weevil, Zimmerman Pine Moth andCooley Spruce Gall Adelgid infections, each to varying extents. For the past two years I have been treating for the weevil only using pyrethrum and insecticidal soap. This seems to have been fairly effective but given the “new” pests, I think that I need to use a “stronger “ control and hopefully effective on all of the pests.
I am considering the following products:
MICROBIAL:
Spinosad
Monterey garden insect spray (0.5% A&D)
Bt
None specific for these pests
Pyrethrin:
Pyganic: listed for weevils and moths
Blends:
Monterey garden insect spray RTU (K salts of FA’s .94%, spinosad
A&D .005%) (listed for weevils, moths and adelgids)
* will probably combine with an insecticidal soap.
Do you know of anyone else who has used these products to control these pests and do you have any suggestions as to which may be the most safe and effective?
Thank you for your time and consideration.
Oceana County Michigan
Expert Response
Effective white pine weevil control involves timing your applications correctly and make contact with the insect. For white pine weevil, this is late March/early April and should be just before the adults begin to lay eggs.
BT will only provide relief against Zimmerman Pine moth larvae that are small. Spinosad is a pyrethroid and would be acceptable for any of the pests on your list. Pyganic would work too. While I'm not familiar with particular trials comparing efficacy of Pyganic Vs Spinosad for white pine weevil, Spinsoad is usually the more toxic of the two.
Another alternative is to apply a systemic insecticide such as imidacloprid.
If following the label application rates and using proper PPE, all would be safe to apply on trees.
See this article for additional information: https://www.canr.msu.edu/news/control_white_pine_weevil_in_early_spring
BT will only provide relief against Zimmerman Pine moth larvae that are small. Spinosad is a pyrethroid and would be acceptable for any of the pests on your list. Pyganic would work too. While I'm not familiar with particular trials comparing efficacy of Pyganic Vs Spinosad for white pine weevil, Spinsoad is usually the more toxic of the two.
Another alternative is to apply a systemic insecticide such as imidacloprid.
If following the label application rates and using proper PPE, all would be safe to apply on trees.
See this article for additional information: https://www.canr.msu.edu/news/control_white_pine_weevil_in_early_spring
