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White pests on holly turning leaves black #874638

Asked June 25, 2024, 1:07 PM EDT

This is a follow-up on white pests on two large green bushes, which seem to be on my holly bushes also. I believe they have been on the holly longer. I dismissed them, at first not recognizing the tiny things as pests and now my holly looks like it’s dying. The third photo shows dead branches of one of the hollies. The second photo shows contrast between the healthy green leaves and the dying branches below. The pests are now on the green bushes (from my previous post) and I would like to know how to get rid of them before they kill the holly and spread to even more plants. There is a Japanese Maple between the infested holly and the green bushes and a Dogwood close by. I’m hoping for an earth-friendly remedy, but will use chemicals if it means saving the holly bushes. Thank you.

Oakland County Michigan

Expert Response


Hello,

Based on your images and your description of the problem. This appears to be Cottony camellia scale: The adult females are about 1/8 inch long but they produce long white egg masses behind them, so they appear much larger. These egg masses are laid on the undersides of leaves and crawlers will hatch and feed throughout the summer. Their feeding results in large quantities of honeydew, which in turn leads to development of black sooty mold. OR this might be Japanese Wax Scale: These pests appear as white, waxy blobs up to 6 mm in diameter on limbs and twigs, often accompanied by sooty mold. The sooty mold would explain the black leaves in one of the images.

For a confirm and precise identification of the problem, I recommend you send all your images by e-mail to the MSU Plant & Pest Diagnostics Lab. The experts there can also provide you with the best treatment options. Their email is <personal data hidden> - Please include your name – The lab will let you know if they need a sample sent. FYI – The lab may also ask for additional images too.

Their website is at this link:

Plant & Pest Diagnostics (msu.edu)

Their Contact Information is at this link:

Contact Us - Plant & Pest Diagnostics (msu.edu)

This link will explain the details on submitting a sample to MSU Plant & Pest Diagnostics Lab:

Submit Samples - Plant & Pest Diagnostics (msu.edu)


I hope this helps!



An Ask Extension Expert Replied June 25, 2024, 4:10 PM EDT

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