The Great Cankerworm Count. Help us conquer the canker.


Want the cankerworms to stay away?

So do we! We hope that increased monitoring will enable us to proactively band in areas that need it and keep the numbers low.

​​Become a Citizen Scientist!

We think you can help! Become a citizen scientist this winter and help us collect data on cankerworms. We will send your data to Clemson University to analyze​. With your help, we hope to understand the cankerworm population in Charlotte and possibly predict the next infestation.

Ready to get started? Follow these steps.

Pick one large tree in your yard. Wrap a string or tape measure around the trunk approximately 4 ½ feet from the ground. Enter the length (circumference) in inches on the form.

If you're really excited about counting, feel free to check once a week in February and record the numbers you are seeing. Remember to squish the moth after you count it so it doesn't get counted twice.

Super quickoOption! If you don’t have a lot of time, check once in February and submit the information to us.

Once you've finished tracking, enter your data online, or send it to us by mail, by fax or via email.


The Great Cankerworm Count
701 Tuckaseegee Road
Charlotte, NC 28208

BY FAX at 704-336-4444


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Additional resources

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Training resources

The information below provides instructions on how to band your trees and what to look for as you participate in The ​Great Cankerworm Count.

​​How to band your tree

Assistant City Arborist Laurie Reid demonstrates how easy it is to band your own tree.

​What do cankerworms look like? 

Use squares to estimate how many moths are on tree bands that are full of moths.


Trapped moths often lay their eggs on the tree band


​​Why band your trees?

Find out how cankerworms threaten tree health ​and why banding protects them.

​​How to track cankerworms

Learn how to measure your tree and estimate how many moths are on your band.

​​What do cankerworms look like? 

An adult cankerworm on a cre​pe myrtle


An adult cankerworm trapped in Tanglefoot on a tree band



IMPORTANT: You must use the SAME browser on the SAME device in order for the form to work properly. We recommend bookmarking this link if you choose this method:​​ 


Just download, print and follow the instructions.


Measure the circumference of the tree trunk to determine how big around it is. Just wrap a string or measuring tape around the tree trunk at approximately 4 1/2 feet above the ground. Make sure it's straight and tight around the trunk. If you're using string, cut it where the string overlaps and then measure it. Enter the length in inches on the form provided.​​


You can hire a professional to install the band(s), or you can do it yourself. 

List of local retailers that sell tree-banding supplies​

Instructional video on how to band your trees

Tree-banding instructional brochure​​


You have two options for entering your data:

​​​​Online form  - This form will save your data so that you can come back to it each week to enter more data. IMPORTANT: You must use the SAME browser on the SAME device in order for the form to work properly. We recommend bookmarking this link if you choose this m​ethod:​​ 

​​​Printable form - Download this form​ and follow the instructio​ns.​


- ​Start tracking only when you start seeing moths on your band. There are two ways you can track how many cankerworms are on your band.​

Method #1: Count all the moths on the band.
This method works well if you only have a few moths.

Method #2: Estimate using squares
If the band is covered with moths, it may be easier to estimate them by using 3-inch square holes cut out of a piece of paper.

How do I estimate using squares?
Print out this template and cut out the three-inch squares provided. Place the paper in random places on the band and count how many moths are inside the holes you just cut out. The number of squares you use depends on the circumference of your tree.

  • ​​​Less than 31 inches - Use three squares

  • 31 to 62 inches - Use four squares

  • More than 62 inches - Use six squares

Select different areas to count each week. To ensure you don't count the same moths twice, use a stick to mash or squish the moths.