Knowledgebase

caterpillars or disease? #872214

Asked June 08, 2024, 4:53 PM EDT

Please see the pic of a maple leaf. Yes, we have plenty of spongy moth caterpillars, but none of the other plants they have attacked have these spots on the leaves. Does this tree have a disease/infestation in addition to the caterpillars and if so, how should we proceed? Thank you.

Ulster County New York

Expert Response

Barbara,

Looks like tar spot.  You can apply a fungicide making sure the entire leaf is covered. 

As an ongoing measure, rake up fallen leaves and destroy them.  In the Fall makes sure all leaves are raked, removed and destroyed.  The fungus does survive throughout the winter, overwinter.  Attached is a fact sheet.

tarspotofmaple.pdf


Good luck,

Cynthia B, MGV

An Ask Extension Expert Replied June 10, 2024, 11:43 AM EDT

Thanks. This is very helpful.    the pdf is not clickable. 

 

From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask Extension
Sent: Monday, June 10, 2024 11:43 AM
To: Barbara Lawrence <<personal data hidden>>
Subject: Re: caterpillars or disease? (#0142132)

 

The Question Asker Replied June 10, 2024, 11:49 AM EDT

http://plantclinic.cornell.edu/factsheets/tarspotofmaple.pdf

An Ask Extension Expert Replied June 10, 2024, 11:57 AM EDT

Thank you... I have done a bit of googling since you told me what it is.    This link is broken at the Cornell end it appears.

 

From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask Extension
Sent: Monday, June 10, 2024 11:57 AM
To: Barbara Lawrence <<personal data hidden>>
Subject: Re: caterpillars or disease? (#0142132)

 

The Question Asker Replied June 10, 2024, 11:59 AM EDT

Hi Barbara, I couldn't tell if you ever received the PDF in a format you could open. Hopefully the attachment works this time. Let us know if you need anything else.

thanks,

Holly



An Ask Extension Expert Replied June 10, 2024, 6:04 PM EDT

You are great!  Thank you.

 

From: ask=<personal data hidden> <ask=<personal data hidden>> On Behalf Of Ask Extension
Sent: Monday, June 10, 2024 6:04 PM
To: Barbara Lawrence <<personal data hidden>>
Subject: Re: caterpillars or disease? (#0142132)

 

The Question Asker Replied June 10, 2024, 6:36 PM EDT

Loading ...