Magnolia tree dropping leaves

Question: I have magnolia tree that lost so many leaves last year and is now beginning to loose leaves again. On the advice of bordines ,this spring I use one treatment of bio advanced tree and shrub protect and feed. I am not sure exactly what to do now. This product offers a 12 month protection so I am not sure if I should use it again this year.We planted this tree 17 years ago .The pictures shows what the leaf looks like before it drops. Not sure if this is from bugs or disease.  Any guidance would be greatly appreciated.   Thank you. Kimberly Revers

responder: An Ask Extension Expert Replied June 26, 2024, 12:14 PM EDT
response: Hello,  In your images, the yellow blotches and leaf loss on your magnolia tree could be symptoms of an insect infestation, possibly from magnolia scale insects. These pests feed on the tree sap, excreting a sugary substance called honeydew, which can lead to a black fungal growth known as sooty mold. More information is at this link:   Why is sap dripping from my magnolia tree? - Landscaping (msu.edu)  This can cause the leaves to turn yellow and eventually drop off.  Magnolia scale is particularly problematic because it’s difficult to notice until there’s a significant infestation. The scale insects are usually attached to 1- to 2-year-old branches and are covered by a protective waxy coating. More information is at this link:  Common Insect Pests of Magnolia (uky.edu)  For treatment, timing is crucial. The magnolia scale's young nymphs (crawlers) are more vulnerable to pesticides and typically emerge in late summer. An accurately timed application of contact insecticides, such as horticultural oil or insecticidal soap, can help reduce the scale population. More information is at this link:  Why is sap dripping from my magnolia tree? - Landscaping (msu.edu)  It’s also worth noting that sassafras weevils, also known as yellow poplar weevils or magnolia weevils, can cause similar damage. They chew distinctive holes in the leaves that can lead to significant leaf loss. More information is at this link:  Common Insect Pests of Magnolia (uky.edu)  Before applying any treatment, it’s essential to identify the pest correctly. I recommend consulting MSU Plant and Pest Diagnostics or a certified arborist who can provide a precise diagnosis and suggest an appropriate treatment plan. They can also advise whether another application of the bio-advanced tree and shrub protection and feed product is advisable this season.  Remember, maintaining the tree's overall health through proper watering, mulching, and fertilization can also help it resist and recover from pest infestations.  I recommend you do one of these options: OPTION 1:  For a confirmed 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.   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 of submitting a sample to MSU Plant & Pest Diagnostics Lab:  Submit Samples - Plant & Pest Diagnostics (msu.edu)  OPTION 2:  You can consult a local arborist for a more detailed onsite assessment and personalized advice. To find an arborist in your Zip Code, go to this link:   Find an Arborist (treesaregood.org)  I hope this helps!

responder: The Question Asker Replied June 26, 2024, 10:10 PM EDT
response: Thank you so much for all that i for all that information.  I will definitely get in touch with them!


Please note: message attached

From: "Ask Extension" <ask>
To: "Kimberly Revers" <krevers>
Subject: Re: Magnolia tree dropping leaves (#0144642)
Date: Wed, 26 Jun 2024 16:14:35 +0000</krevers></ask>