What Every Homeowner Needs to Know About Their Aging Trees


 Cankerworm Page

Cankerworms 2017/2018

If you are just visiting this page, you might want to first look at Cankerworms 2007-2008 I gave a fairly detailed program about cankerworms, and then wrote up most of the text for this web site.   What you see directly below goes back to the first of the year (2012).  If you want to see what happened earlier, go back to the Cankerworm 2011 in the sidebar to the left.  The  link on the left for 2016 goes all the way back to 2010 as one long posting.  Since it is there, I will just leave it, but my intention is to include current information about cankerworms on the specific page for the year or dates indicated.

  Jack McNeary

December 27, 2018

Cankerworms will be out soon and I will start a new page with the cankerworm activity for 2018 and 2019.  I see many traps up too early this season.  A few of the entries below are posted on my home page.

I should have posted this before Christmas because many trees had not shed nearly all of their leaves.  We happen to have a Pin Oak that the city planted in the planting strip at the road.  This is really annoying because it holds its leaves on long after all the other trees have dropped them.   Here I had all the leaves cleaned up and then a little rain and wind and the Pin Oak went ahead and dropped all of them.  I have seen some pin oaks hold their leaves well into the winter and close to spring before the new buds pushed the older leaves off.

Many people  had bands up a month ago and also had applied the tanglefoot.  The old rule was that one should put the traps up around Thanksgiving time, but what I have observed over the years is that the cankerworms have been arriving gradually so that January is the month when most cankerworms are trapped.   Earlier in the archives here I keep, the day of the greatest trapping was on or about Christmas day, ie December 25th. map of cankerworm activity    (need to fix this error) Today, two days after Christmas, there are lots of traps, lots of leaves up on the traps which allows the cankerworms a bridge to go further up the tree and lay their eggs.

This week, I will be checking street trees to see if there is any activity.  jmm


December 18, 2018 Tuesday
 Today as I was driving up Queens Road West, I saw banded trees, both private and public street trees with Tanglefoot on them.  Many of these traps were loaded with willow oak leaves.  Many trees have not dropped all their leaves, and the city has not blown the leaves off the median yet.  If the trap is covered with leaves the female cankerworms will walk right over the trap.
   Last year the insects did not start going up the tree trunks until later.  I will check the exact date later.

December 9, 2018 Sunday
A word of caution about the snow, ice, sleet storm we are getting today and tomorrow.  Trees normally have lost their foliage by this time of the year, and many trees are still in full leave.  A wet snow or ice on leaves creates a tremendous load on the root system.  Many of our large trees have a root system confined in a small space, and a canopy that under ideal circumstances spreads in the air to as much as 3 times the drip zone. (photo of Drip zone)  Where I live, our planting strip between the sidewalk and the street is 11 feet wide.  This is a lot greater than most trees have because we live on a thoroughfare. Some of the planting strips in Charlotte are 3 to 4 feet in width, and no where near 11 feet wide.   What this ends up looking like is an upside down lollipop for a root system, tall trunk, and considerable foliage.  To make bad matters worse,
 we have lots of willow oaks and they are particularly susceptible to root rot.  Inonotus happened in particular. Link here for Weeping Conk ... Inonotus draydeus  


November 1 through December 3, 2018 Monday

Several things to catch up on .... lots of things have happened. 

I heard someone say that it was time to get the cankerworm traps up now.  I radically disagree for several reasons.  The first is that many trees are still loaded with leaves and your traps
will be covered up with falling or it not that and you have the Bug Barrier trap where the leaves are protected from falling leaves, leaf blowers will do a thorough job blowing leave up under the trap.
The last point is that the season last year was radically off.  In the Myers Park area some large trees did not capture any or very few cankerworms.  As I have suggested in the past do not put
up traps until you are sure you will have an infestation.  link here later







September 11, 2018
I should have posted this two weeks ago.  I saw a type of cankerworm parachuting down from the willow oak in my back yard.  If I can find another, I will surely photograph it.  Since then there were several more.  This one has the same type of legs as the fall cankerworm but is not.  The color is a distinct ugly green.  The best I can describe is it Chicken S... Green.  We know there are many species of cankerworms and I believe that this would be one of them.  It did have the two sets of legs, one in the front and one in the back.  To my knowledge this particualar insect has no bearing on the fall cankerworm which won’t show up for several months


See disclaimer on home page.  having computer problems

Will get the data back soon.  Today is Jan 5, 2018  All info about cankerworm is on main page.  It has been a very strange year.  Go to Home page

December 17, 2017 Sunday
No sign of the Cankerworms yet.  I have not put up my tar paper but will tomorrow if I can.  I have seen some leaves and trash blown up into the tree traps but most of the leaves are down now and soon  I expect the cankerworms even though at my home it has not dropped below 28 a single night. 


December 14, 2017
I am reluctant to make a prediction on exactly when the cankerworms will start crawling.  Where I live, it is not as cold as it must be at the weather station at the airport.  They get readings of 26 and I get 28 plus.  Maybe they will emerge soon, maybe not.

December 12, 2017 Tuesday
Don’t jump the gun on the cankerworm traps.  I see individuals and the city banding the trees in the median on QRW.  I also see trees with loads of leaves, and now I see traps with Tanglefoot and leaves plastered to the trap.

We still have a few days before the cankerworms move.  In the county, maybe, but here in Charlotte, proper, the cold has been barely below freezing.  The predictions from a week ago are a few days late.  I expected brutal cold a few days ago, and I do think it will be cold enough soon.
The worms will start slowly and if you are a homeowner and have the band up you can put a 1 inch band around the tree and wait until you see several cankerworms.  If you can wait until the leaves do fall and then put ample Tanglefoot on the trap you will save yourself some grief and the trap will be more effective.  Unfortunately, the city and the companies that you contract to are between a rock and a hard place.  Get a pair of old tweezers and remove the leaves stuck to you trap one at a time.

December 6, 2017
We are expecting 25 degrees this Saturday and 21 for Sunday.  Monday 33, and then on Tuesday 24, December 13th again 25.  This should get the female cankerworms started.  The leaves will be mostly gone so now all you have to do is worry about the leaf blowers.  I have neighbors who use these large lawn care companies and are using 3 or more leaf blowers at a time.  I wear ear protection muffs when I go out in my back yard.  The noise is deafening.

It might be interesting to note the actual dates that the cankerworm has emerged in the past.
I plan to go back through the records and see.  I marked the date I first saw the starting date in red so it will not be hard to track.  On the left sidebar one can go back ten years.


It’s time to start a new page on cankerworm activity.  In the past I have waited until the end of the year to start a new page, but it seems more appropriate to start a page as we get ready to enter the fall cankerworm season.

Interestingly enough today is Thanksgiving Day 2017, November 23rd.  Every year the question comes up about when to start banding.  I started studying cankerworms after Hurricane Hugo slammed Charlotte pretty badly in 1989.  There were trees down everywhere and we have been struggling with cankerworm problems ever since.  When cankerworms started becoming a issue, no one understood their breeding habits, why did the females come out of the ground at a certain time, when did they lay their eggs, where did they lay their eggs.  I first started capturing them on a trap in my front yard and counted them every day, mashed them, and kept a record of their activity.

Over time, when they emerge has been something that has changed, but other than that the cankerworms perform much as they have for millions of years.  On this site, the sidebar on the left will take you back to what I have observed in the past.

Cankerworms are not here yet, so I will add to this page.  Meanwhile it is too early to band your trees unless your trees and your neighbor’s trees are defoliated.

It takes 3 days of temperature around 27 degrees F. for the cankerworms to emerge.

more later


 Charlotte, NC 28205
Phone: 704.618-6214