This is referred to as a magnolia but is nothing like the southern magnolia tree - Ask Extension
What is this disease? Some kind of scale? How do I treat it??? Also, there is shiny sap on many of the plants below the magnolia.
Knowledgebase
This is referred to as a magnolia but is nothing like the southern magnolia tree #878558
Asked July 24, 2024, 12:00 PM EDT
What is this disease? Some kind of scale? How do I treat it??? Also, there is shiny sap on many of the plants below the magnolia.
Auglaize County Ohio
Expert Response
Hi Denise,
It appears that your magnolia is infested with Magnolia Scale.
As the name suggests, magnolia scale feeds on magnolia trees, particularly star magnolia, saucer magnolia, and the many popular hybrid lily magnolias. Native magnolias such as sweet bay and cucumber tend to be less severely affected.
What you see on your tree right now are the female scale insects protected under a white waxy/powdery coating. The sticky substance on the plants below the tree is called 'honeydew' and is excreted by the scale insects as they feed.
Magnolia scales give birth to live young called "crawlers" that emerge from under the female insect from late summer through the end of September. Insect life cycles are dictated by heat so the emergence of crawlers will vary from year to year.
While the presence of magnolia scale doesn't necessarily pose an imminent threat, extensive feeding by a large population often leads to yellowing of leaves and twig dieback. Over time, an untreated population of magnolia scale may lead to the decline of the tree.
Magnolia scale can be managed mechanically or chemically. If the infestation is within reach and fairly light, it can be removed by gently rubbing or scrubbing the insects off the affected branches. Removal of entire branches may be called for if the infestation is particularly heavy.
Timing is a critical factor when using chemicals to treat magnolia scale. Scale is most vulnerable at the crawler stage - late summer to early fall - when it can be treated with contact insecticides. It may require more than one treatment and large trees may best be treated by professionals. Spring is the best time to apply systemic insecticides. This article from the University of Kentucky provides more detailed information about chemical treatments:
https://entomology.ca.uky.edu/ef431
Here's another excellent article about magnolia scale from the University of Massachusetts.
https://ag.umass.edu/landscape/fact-sheets/magnolia-scale
If you decide to seek professional assistance, the following link takes you to the Ohio Chapter of ISA where you can find certified arborists in/near Auglaize County.
https://ohiochapterisa.org/aws/OCISA/pt/sp/trees4ohio_find-an-arborist
I hope this information helps you solve your scale problem!
It appears that your magnolia is infested with Magnolia Scale.
As the name suggests, magnolia scale feeds on magnolia trees, particularly star magnolia, saucer magnolia, and the many popular hybrid lily magnolias. Native magnolias such as sweet bay and cucumber tend to be less severely affected.
What you see on your tree right now are the female scale insects protected under a white waxy/powdery coating. The sticky substance on the plants below the tree is called 'honeydew' and is excreted by the scale insects as they feed.
Magnolia scales give birth to live young called "crawlers" that emerge from under the female insect from late summer through the end of September. Insect life cycles are dictated by heat so the emergence of crawlers will vary from year to year.
While the presence of magnolia scale doesn't necessarily pose an imminent threat, extensive feeding by a large population often leads to yellowing of leaves and twig dieback. Over time, an untreated population of magnolia scale may lead to the decline of the tree.
Magnolia scale can be managed mechanically or chemically. If the infestation is within reach and fairly light, it can be removed by gently rubbing or scrubbing the insects off the affected branches. Removal of entire branches may be called for if the infestation is particularly heavy.
Timing is a critical factor when using chemicals to treat magnolia scale. Scale is most vulnerable at the crawler stage - late summer to early fall - when it can be treated with contact insecticides. It may require more than one treatment and large trees may best be treated by professionals. Spring is the best time to apply systemic insecticides. This article from the University of Kentucky provides more detailed information about chemical treatments:
https://entomology.ca.uky.edu/ef431
Here's another excellent article about magnolia scale from the University of Massachusetts.
https://ag.umass.edu/landscape/fact-sheets/magnolia-scale
If you decide to seek professional assistance, the following link takes you to the Ohio Chapter of ISA where you can find certified arborists in/near Auglaize County.
https://ohiochapterisa.org/aws/OCISA/pt/sp/trees4ohio_find-an-arborist
I hope this information helps you solve your scale problem!
Thanks soooo much
