What Every Homeowner Needs to Know About Their Aging Trees

Where did all the Cankerworms go in the spring of 2019


 Cankerworm Page

Info 2008_Jan 2009

Status of cankerworm activity from December 6 2007 to February 10 2009

February 10, 2009
Today as on the last two days I have seen no female cankerworms.  This is about the normal time that the cankerworm activity has stopped in previous years.  Certainly, they got started late this year and the count will be down.  Shortly I will add up the totals and compare them to other years.

Also I will add some documents from years past, I suppose we could call them archives.  Few people would want to refer to them, but there might be someone out there might want to refer to that information.  In some ways this has been a scientific study but my whole life it not evolved in studying the fall cankerworm.  The first years it did make a difference when I was running a tree service and also having a child in college.  December was a rather profitable month for a number of seasons and in fact even now the work done with banding trees must be a nice boost to the companies who push cankerworm treatment.

We have a respite for a couple of months and I will add information as we get close to that time.  The traps will lose their stickiness and the insects will start crawling in early April.   Here are some internal links.   A second link refers to spraying the trunk if we have a heavy migration of insects back up the trees in the spring.
I will report more later  .  Feb. 17th, 2009

February 9, 2009
0 cankerworms today

February 8, 2009
0 cankerworms today

February 7, 2009   Sunday
4 cankerworms today  I was out of town and there were a total of only four female cankerworms since Thursday.

February 6, 2009

February 5, 2009

February 4, 2009
Thursday  I left town early so did not count the cankerworms.  Next report is for Sunday.  In years past the worms stop in early February.  This year they started late, but seem to be about finished for the year.

February 3, 2009
3 cankerworms today

February 2, 2009
6 cankerworms today

February 1, 2009
3 cankerworms today

January 31, 2009
2 cankerworms today

January 30, 2009
5 cankerworms today
Clear and cold around freezing should warm up well.

January 29, 2009
5 cankerworms today
Freezing in am up around high 50s in afternoon clear pretty day.

January 28, 2009
11 cankerworms today

January 27, 2009
14 cankerworms today

January 26, 2009
11 cankerworms today
Overcast and raw.  Early morning low 30s  mid day  46 f.

January 25, 2009
25 cankerworms today
Sunday mild in AM around 42 mid afternoon overcast

January 24, 2009
24 cankerworms today
Very mild today got to almost 60 degrees

January 23, 2009
2 cankerworms today

January 22, 2009
3 cankerworms today

January 21 2009
2 cankerworms today

January 20, 2009
43 cankerworms today
Today, or better, last night we had a couple of inches of snow, and the number of cankerworms surprised me. The temperature this morning at 7:30 was 27 degrees and at noon it is at freezing, 32 degrees F.

January 19, 2009
3 cankerworms today.
Below freezing at 31 degrees at 7:00 am.... overcast today calling for rain and then snow tomorrow.

January 18, 2009
2 cankerworms today
about 39 degrees in early morning.

January 17, 2009
10 cankerworms today

January 16, 2009
10 cankerworm today
The temperature got down to 11 or 12 around most of Charlotte. Here where I live under a lot of trees it was 17 degrees. It is always a little less extreme here.

January 15, 2009
12 Cankerworms today

January 14, 2009
36 Cankerworms captured today
Clear and fairly cold to day, very cold low of 16 expected tomorrow. Does not usually get as cold as is forecasted. I expect it might be 20 degrees. We will see. Also I do not think the cold slows the worms down. 29 degrees at 7:00 am, at noon 44 degrees. Yesterday was similar

January 13, 2009
39 Cankerworms captured today

January 12, 2009
73 Cankerworms captured today
For some reason I forgot to count Sunday, yesterday. Since the days are similar in temperature and so forth I divided the number of insects by 2. I actually counted 146 insects at 11:00 AM. 43 degrees and clear ... Full moon for whatever that is worth.

January 11, 2009
73 Cankerworms captured today

January, 10, 2009
138 Cankerworms captured today
Temperature 12:00 56 degrees ... clear day was 33 degrees at 6:00 am

January 9, 2009
379 cankerworms captured today
Temperature at 11:00 am 42 degrees F ... was 30 degrees earlier in am 

Today we have a rather dramatic increase in cankerworm activity. I captured 379 female insects in the trap. That is more than ten times an increase over what I would have considered the “normal” count for recent days. I suspect that two days of mostly rainy or wet weather is what has slowed them down. The heavy winds of yesterday and the drying of the air caused them to come out in force.

January 8, 2009
17 cankerworms captured today
Temperature is around 44 degrees F at 11:00 am overcast but dry

January 7, 2009
13 cankerworms captured today
Very windy all day and evening long

January 6, 2009
4 cankerworms capture today
It rained off and on all day today. Everything is very wet.

January 5, 2009
22 cankerworms captured today
It appears to me that this fall most any trap will work. I am not a fan of the plastic Bug Barriers. I have not seen but a few insects get into the three inch band of Tanglefoot on my trap. They all seem to get stuck in first 1/4 inch. In all preceding years we have had heavy infestations, and the insects overwhelm the Bug Barrier traps. If the Bug Barrier trap is installed exactly right there will be four inches of a not very sticky material to trap them. As the season progresses and sometimes before, dust and leaves will gather inside them. You can prove this by sticking your finer up behind one. If we have a heavy infestation, there is just not enough surface area to capture all the insects. To compound the problem many traps are put on incorrectly.

They are easy to put up, but pricey.

This year the Bug Barrier traps should work as long as things do not change radically. Once April gets here, both types of traps need to be inspected to see if the sticky stuff is still working. Tarpaper traps will absorb some of the Tanglefoot also and will not capture insects in the spring unless a wide and thick band of Tanglefoot was applied in the fall.

January 4, 2009
22 cankerworms captured today

January 3, 2009
42 cankerworms captured today

January 2, 2009
18 cankerworms captured today

January 1, 2009
Happy New Year to everyone...
28 cankerworms captured today
It was very windy yesterday and pretty cold today down about 28 degrees F. here over night. Based on yesterday’s numbers I expected today to have a larger count. Be interesting to see what tomorrow brings. It is very clear and pretty cold. Now it is in the mid 50’s and I checked the trap at 10:30.

December 31, 2008
124 cankerworms captured
Will now we are on to something. I counted and mashed 124 cankerworms in the trap this morning about 10:30. The previous day December 30th I checked the trap at about 11:00 AM. In general I try to check the trap mid morning.

I also have observed over the years that the insects tend to come up to the trap on the south side of the tree first and that is true this year also. They also come up mostly at night or maybe early morning and prefer a clear day. At about 4:30 yesterday I checked the trap and found four six insects. Then of course this morning there were 124 cankerworms. Our total for December this year is 279 captured insects. That is way down from the 1987 insects captured in December 2006.

I do find that 124 is a very large number, and I expect that pace will continue for some time.

December 30, 2008
24 female cankerworms today (no this is not a mistake just coincidental)

December 29, 2008
24 female cankerworms today
This a pretty dramatic increase in cankerworm activity. The message below for December 28 is an accumulation of five days activity. I personally expect to see the numbers stay the same and probably increase for about 20 days. In the long run,
though, I still think there is less activity than last year and certainly the year before that.

December 28, 2008
75 female cankerworms today
I have been out of town since Tuesday, December 23rd so have not checked my trap until today which is Sunday. At the time I left I guessed that I would have about 6 female cankerworms per day. We left at 5:30 am in the morning for a long Slog to Detroit and as you might guess ran into some weather problems. Sure glad I live in the South.

Anyway, at about 11:00 this morning I counted 75 females. There also were lots males stuck to the trap (I do not bother counting them) and some of the trapped females had laid eggs on the tar paper. I did not count for five days, and that is an average of about fifteen cankerworms a day. They are doing what they are supposed to do, just seem to have started later. I still think the migration is down from previous years and if so that is a good thing.

Last season we concluded that the aerial spray did a pretty good job. I have no plans to be gone for a long period of time for the next few months so should post results daily.

December 22, 2008
2 cankerworms

Today is Monday and it has been quite cold. I believe it was 23 degrees and is supposed to go to 17 tonight. On Sunday
there were 6 female cankerworms and today the 22nd there were 2 female cankerworms. I will be out for a few days and
will not be able to check my trap. We are defiantly late this year.

December 21,2008
6 cankerworms

December 20, 2009
4 cankerworms

Today there were 4 females in the trap. This is pretty typical. It will not surprise if we continue to see feeding at an increasing pace. One good bit of news is that our drought is officially over as of today. The subsurface water is still needed and our mountains are very dry.

December 19, 2009
I have been late providing this information. Part of that has been some minor computer problems, but the big reason is that there is little activity. I expected that we would have the annual migration of the female cankerworms in late November. We had a severe cold snap back over a month ago and I expected to see activity in a week or so.

Last year (fall 2008) the first date that I saw female cankerworms was December 6th. The year before that was much earlier and was on November 16 2007..   xxxx dec2009 ************************************************************

Here is a quote from an earlier page which sheds some light on what we typically see:

This quote was posted on December 6th 2007.

Still very little activity. I have found 2 female cankerworms on one tree and one on another. I do not expect to see the migration start until it cools down again. To have it 80 degrees for two days in a row in December is really extreme. For what it is worth, last year I captured one cankerworm on November 16th 2006 and a total of 26 for the month of November. In December it was a different story in that I captured 1,987 and in January 3,901. In February there were 27 insects trapped. Later in the spring there were thousands trying to go up the tree, and I estimated there were at lease 1,000 insects on the tree. Had those insects been allowed to go all the way up unimpeded, who knows how many others would have followed.

I was out of town for a few days this past week and left in the driving rain on Thursday. When I returned on Sunday December 14th I found three females. I saw two more on December 16th and two more on December 19th.(today) So that is it. I suppose it is possible for the numbers to pick up dramatically because that is the way they always do, but at this time I believe that the spraying was effective. I reserve the right to change my mind as the days go by. In the past December and early January are the months with the most activity.

jmm 12202008

Below the red asterisk is the information from 2007 and 2008. Above this line will be Fall of 2008
************************************************************************************* ***

Fall 2008   November 22     First Entry for the Fall Cankerworm Season.

Below this entry is information from the previous 2007 and 2008 season.  The way the insects behave is the same as it has been for thousands of years.  Different factors like water, temperature will cause variations.  If you want to read the details then follow the links backwards.

I have been out of the country so am a little late putting up my traps this season.  We have also had a really good cold snap so I suspect that the female cankerworms will be moving up the trees shortly.

I always band one main willow oak in my front yard with tarpaper and put a 6 inch band of Tanglefoot on it.  I have done that and so far have seen no cankerworms.  It takes some time to do a neat job of installing the tar paper so I have developed another method which I used last year and thought that it caught as many insects as the tarpaper trap.  I have a roll of plastic wrap that is used commercially to wrap packages.  It is much like Saran Wrap.  I will post a picture.

In using this material which goes on in a fraction of the time as tarpaper I make a number of wraps overlapping so that I have about 12 inches of surface area.  I use small one LB containers of Tanglefoot and heat them for 10 to 20 seconds in the microwave.  I then use a spreader much like a paint stirrer but a little thinner to apply the Tanglefoot.  I can throw this away after doing a tree which is handier than having to clean a putty knife.  Either way works as well for applying the Tanglefoot.

The only caution is that you need to be a little careful that you do not rip the Saran Wrap.

Instead of using cotton fiberglass batting material, I simply break off about a 6 inch to 12 inch piece of Saran Wrap and stuff it in any crevices that I feel a cankerworm would find.  The end product is a clear or green (the wrap comes in two colors) wrap around the tree and the Saran “batting” substitute makes the entire operation fairly neat.  I find it easier to put the stuffing material in the upper part of the band and I used a single staple to anchor it in place.  I neglected to mention that I use 2 1/2 inch staples at the start of the wrap to hold it in place and 2 or 3 at the end of the wrap.  I make a fold or two at the start and end to give a little more bulk to hold a staple in place.

Directly below is a letter e-mailed to the local residences.


From: Rusty Bryson

I am forwarding a piece that Jack McNeary provided to me that answers many of the questions that our neighbors have about tree banding the cankerworm problems we have had the past several years.  Jack is a Consulting Arborist and long time Myers Park Homeowners Association Board Member.  He continues to be a wonderful resource to the Association and the neighborhood.
We hope this provides you with some useful advice and answers any questions you may have.

Rusty Bryson
Myers Park Homeowners Association


Here are some thoughts about what we should do about the fall cankerworms this fall and through the winter. 
The City of Charlotte will be banding trees.  Their policy has been to band street trees over 24 inches in diameter that live on the thoroughfare.  Last year as most people know the city contracted aerial spraying for a very large area of 73,000 acres.  In general it was pretty effective.  The weather cooperated, but we are never going to get complete control with spraying.
Will We Need To Band Trees This Season?
The city will be banding the street trees on thoroughfares again this year.  The question that is being asked is that if the city sprayed last year can we skip banding this year on residential trees.
The answer is no.  Residential trees probably will need banding.  If you had a very low or no infestation of cankerworms last fall, then you might elect to not band your trees.  The city trees that have tar paper bands and Tanglefoot on them can serve as a guide.  If you live close to a properly banded tree, and there are no female cankerworms crawling up the trunk then you do not need to band. 
If you see insects starting to crawl up banded trees after the first hard frost then you better get your bands up immediately.  If you are having someone else helping you with banding, that might be too late if they cannot get your job done in a few days.  If you are doing the job yourself and have your materials ready to go, you can install the bands immediately.  If you see insects crawling, then you can delay banding until the last minute.
When Will the Cankerworms Arrive
Last fall the insects started crawling December 6, 2007.  On the tree I observed, there was one insect on the 6th, one on the 8th and two on the 11th.  The year before, 2006, the insects started up the trees on November 16, 2007.  Again, we need a good hard freeze of about 27 or 28 degrees to bring them out of the ground.  There will be some variation since I live in the city proper, and it is a few degrees warmer than in areas outside the city.  Note that the weather report says the temperature will be 26 degrees F. on Wednesday morning November 19th.  It is very possible that will be cold enough to trigger the migration up the trees to lay their eggs.
Do I Need to Band All the Trees in My Yard
Below are the host trees for this area that I know about:
Willow Oak, White Oak, Southern Red Oak, Sugar Maple, Japanese Maple, Siberian Elm, Lilac (rare here in the south), Flowering Cherries, Dogwoods.  Farther north the American Elm trees are a favorite host for the cankerworm.  Interesting, that here the cankerworms do not seem to be interested in elms.
Trees that are not affected in our area and should not be banded are:
Tulip poplar
Sweet gum
Pine trees  (all conifers)
Note dogwoods and Japanese maples are both under story trees, and often are attacked by cankerworms crawling down from other trees, or parachuting down on silken threads. Cankerworms are close kin to the silkworm.
Don't waste time and money on banding trees that do not need it because the insects never feed on them.  
Materials to Use
Tarpaper and Tanglefoot are the preferred materials required by the city.  Other materials such as the plastic Bug Barrier work, but the surface area for trapping insects is very small and the sticky stuff dries up before spring.
I am told that the price of tarpaper is up quite a bit this year, but if you are doing the job yourself, below are some comments.
The tarpaper band should be at least nine inches wide.  The band of Tanglefoot should be six inches wide and 1/8 to or an inch thick.  Apply the Tanglefoot to the lower part of the band so that if you need to reapply later in the season, there will be room above the original Tanglefoot.
Last year I used plastic Saran like wrap around some of the trees in my yard and found it worked very well.  It was much easier and quicker to install around the tree than the tarpaper.  It worked just as well as the tarpaper and required only three staples to hold the last wrap down. On most trees I used little if any batting material.  In fact I just stuffed some wadded up Saran wrap in the voids.  Larger trees might require more batting.
How Long Do the Bands Need to Stay Up?
The bands should be in working condition until mid April 2009.  The initial female insect is captured in the Tanglefoot starting after the first hard freeze.  The first wave of worms will stop about early February.  In late March or very early April just after the insects hatch in the trees there will be thousands of insects wanting to go back up your trees to feed on the tender foliage.  You will need to make sure your traps are working at this time.  Reapply Tanglefoot and if you had Bug Barrier installed you can still smear Tanglefoot to the outside of the trap. 
Jack McNeary
Consulting Arborists



Current Stuff  Spring ... April 1, 2008 until cankerworms have stopped eating our trees for the season.  See Current Stuff Spring


March 31, 2008 Monday

As you can see I have not posted since late February.   This past weekend I checked my traps since I had been out of town.  I saw two very small green worms which I am sure were worms that had hatched from egg clusters that were deposited on the tar paper of one of my traps.  That coincides with last year in that I saw dozens of cankerworms. on March 25th 2007.

What this means is that the worms are hatching all over town in the tops of the trees.  They will feed on the young buds and when they have gotten all they get, the will come down the tree.   Two years ago on the 18th of April 2006, they were defoliating the trees very quickly.  I thought the drought might cause them to come out later, but nature wants them to come out just as the leaves are forming.  In other words, we are right on schedule.

As stated earlier, the city will spray.... probably late next week.  Directly below I have posted a message that I wrote for the MPHA newsletter.  It explains the need for applying more Tanglefoot

March 30, 2008
Residents of Myers Park
Our MPHA neighborhood newsletter will be distributed shortly, however, the cankerworm problem needs attention now.  Some of the small green worms have hatched and are starting to feed on the trees. The City is planning to spray the trees soon, and there is an article in our newsletter that you should read now.
The article below will appear in the newsletter.
Kindest regards,
                    Tom Masters                
Cankerworms Spring 2008 .........
Reapply Tanglefoot
If the Tanglefoot on your cankerworm traps is dry or your traps are damaged by
squirrels, you need to reapply Tanglefoot.  The information below goes into more details.
Charlotte Will Spray for Cankerworm
A contractor for the city of Charlotte will be spraying approximately 63,000 acres for the fall cankerworm in early April.  That is over ten times the number of acres that the city sprayed in 1998.  It will take from four to seven days of decent weather, and the odds of having little wind and no rain for that seven-day period in the early spring are not good.
What that means is that certainly aerial spraying will help, but if you have trees with cankerworm traps that have captured a large number of cankerworms this fall, then you need to be alert.  If the traps are not installed properly, they do little good.  In our opinion, the infestation was erratic this season.  Some people said they had never seen it as bad and others saw little cankerworm activity.  Probably because of the drought, the cankerworm migration started about four weeks later this year than in 2007.
We have observed that the traps that are made with tarpaper and have Tanglefoot applied in a wide band of approximately 6 inches and of an inch thick work best.  Even if you have traps that are installed properly, you will need to reapply some Tanglefoot to the existing band.  The sticky stuff on any trap tends to dry out during the winter and with insects, leaves and dust, the traps loose their effectiveness.
More Bugs Are Coming
In late March and early April, the cankerworm eggs that are the trees will hatch.  The young caterpillars will feed on young buds and leaves and descend from the tree.  They parachute to the ground or crawl down the trunk looking for more food to eat.  Once on the ground they will start looking for food, and they do not care for grass.  The cankerworms start crawling up your other trees and shrubs.  The caterpillars will even climb up telephone poles and the side of your house.  Last season we saw trees where thousands of cankerworm caterpillars crawled up trees and defoliated the trees.  Although the defoliation does not kill the tree outright, it weakens the trees and along with the drought, we have been having, we expect to see an increase in dead and severely weakened larger trees.
The Bug Barrier traps lose their effectiveness when there are a large number of insects for a number of reasons. Squirrels have become very fond of the white batting material and pull the batting out from the trap and use it to line their nest.  Squirrels also will chew on the traps sometimes eating the trapped insects.  Lastly, the sticky material inside the trap dries out quickly with dust and does not cover a large enough area to capture insects in a heavy infestation. The sticky area on the inside of the trap is only two to three inches wide. 
The good news is that one can take Tanglefoot and apply it to the outside of the Bug Barrier trap and still capture a large number of the caterpillars this spring.   The tarpaper trap is likely to have leaves, male and female cankerworm moths, and dust in it.  In addition, the Tanglefoot tends to be absorbed by the tarpaper since it has been on the trees for four months.   It is necessary to put another inch of so of Tanglefoot above the existing Tanglefoot band.
Reapply Tanglefoot
We recommend replenishing the Tanglefoot band anytime after late March.  Last year we started seeing heavy defoliation about the 12th of April.  You will not see insects crawling up the trees or heavy defoliation until about a week or so after the insects first emerge and the City sprays the trees.
Plan to water and fertilize your trees and the city trees that are between the curb and your sidewalk later this spring.  Any trees with restricted root systems will have suffered more than freestanding trees because of the drought.
jack mcneary

For all practical purposes, the fall cankerworm infestation on my tree, and I suspect all trees in the Charlotte, has stopped.   I do not plan to enter information on this site until the middle of March when I will advise people to check their traps and apply Tanglefoot if needed.   It will be required on all traps unless you had a very minor experience.  Remember this is what the caterpillars looked like on one tree last year where a person put duct tape up on the tree backwords.  This is the second part of the infestation that we originally ignored in the early years of trying to stop this insect.


Sat 23=cw=0,  Sun 24 =cw=1, Mon 25 =cw=0. Tues 26=cw=0, Wed 27=cw=0


February 22, 2008 Friday

Every day the numbers of trapped female cankerworms are dropping.  I have attached a few more photos of what does not work.  A heavy infestation will cover four to six inches of Tanglefoot.  So if you only put a two inch band of sticky material, it is not going to trap all the worms.  Here  is an example of the Bug barrier which in this case has about 1 1/2 inches of sticky stuff on the inside of the plastic.  Today it was dried up and not sticky at all.  Notice a few worms on the outside of  the trap.  Lots of insects have been captured in the upper trap in the Tanglefoot.  The photo to the right is a similar trap, but the Bug Barrier has not been installed properly.  Note the bulge of the batting material on the right side of the photo.


Below on the left is another tree where the insects can be seen near the ball point pen.  They are on the outside of the trap moving up to the second trap with the Tanglefoot.  You can see that lots of insects have been captured in the second trap above the Bug Barrier trap.

The photo to the right show a big tree with a band that is entirely too small.  Also the Tanglefoot is not very thick and this type of insulation material absorbs the Tanglefoot quicker than any other product I have observed. This is a very large and beautiful tree.  Whoever installed this trap did a disservice to the client.


The photo below is one of the experimental traps I put up in my own yard.  About two weeks ago I added additional Tanglefoot above the original band.  The older band is about 4 inches wide and I suspect that a few cankerworms got past the band.  So far I have not caught any in the newer, recently applied Tanglefoot, but I should have installed it earlier.  This plastic wrapping works pretty well and is certainly easier to install around the tree than the tarpaper.  I did not time it, but I’ll bet it took about one minute to wrap the plastic and put in a few staples.  I also used some extra plastic wrap to stuff in a few voids to keep the cankerworms from crawling up underneath the wrap.  I had to be a little careful putting on the Tanglefoot so that I did not rip holes in the wrap.  You can buy a roll of this or similar wrap for about $10.00 and could wrap dozens of trees with one roll.



Thur 1 4 =cw=10,  Fri 15 =cw=8, Sat 16 =cw=18,  Sun 17 =cw=10, Mon 18 =cw=9. Tues 19=cw=4, Wed 20=cw=4, Thur 21= cw=5 Fri 22 =cw=0

February 13, 2008 Wednesday

Today is rainy and about 45 degrees F. in the morning.   There were only two cankerworms on the trap and the rates have been declining for a number of days.  I think the migration is about done.  I suppose many of you have noticed that the worms seem to come up on certain sides of the tree.  The first cankerworms came up on the southeast side which would have been the warmest side of my particular tree.  Later the opposite side of the tree had the most insects.  I have observed this for a number of years.

As stated earlier, I check the trees daily but do not necessarily enter the data daily.  In general, I make some addition to this site once a week.   I will continue to do that and will certainly keep an eye on things in the later part of March.

Tues 12=cw=17   , Wed 13=cw=2

February 11, 2008 Monday

Below is a photo of a willow oak with two bands on it.  I illustrates why I do not like the Bug Barrier.  Certainly it works sometimes, but as this photo shows, squirrels really can tear them up.  They seem to have learned and are teaching their young ones how to get the batting material out for their nest which seems to be the case in this photo because there does not seem to be much cankerworm activity.  I have seen them break off the plastic to get at the insects that are stuck.  They have been observed eating the cankerworm insects that are stuck to the trap.

I am often puzzled why people put out more than one trap.  In this case I suppose the homeowner paid someone to put up the Bug Barrier trap, and when the city came by they installed the other.  That does not explain why I will see two Bug Barrier traps together.  There is a lot more labor with the Tanglefoot and maybe the extra Bug Barrier material is less than the labor to put up the Tanglefoot trap.

If the squirrels get the traps two or three would not work.


Directly below is the the last few days count for cankerworms.  Cw stands for cankerworm as I suppose anyone can see.  I wrote down Fri and Sat information on something that I left home.  Will add to it shortly.


Fri Feb 8=cw=17,  Sat Feb 9=cw=27, Sun Feb 10=cw=35    ,   Mon Feb 11=cw=26,


February 7, 2008 Thursday

I do not spend all my time worrying about cankerworms and post this information once a week, usually over the weekend.  I also do not send this link out to all the people who could get it.  Our neighborhood mailing list goes to at least 875 people plus I have a pretty extensive list of people interested in tree issues.

I have a short list of people who I do notify and can put anyone’s name on it who wants to be included.  Just drop me an e-mail.

Tue. Feb 5 = 24, Wed Feb 6 = 12,  Thur Feb 7 = 26


February 4, 2008 Monday

Lots of worms out there!!  Everyday, as I drive up and down the streets I see traps that have lots of insects on them.  I think the season just got started late.  I suppose the drought could have had a lot to do with that.  The count is as follows


 Wed Jan 30 = 52, Thurs Jan 31 = 26, Fri Feb 1 = 38, Sat Feb 2 = 26, Sun Feb 3 = 47, Mon Feb 4 =97,

I think the cankerworms are on the downswing.  Last year they were finished after the first week in February.  After they stop crawling, I will compare last years count with this years and post it.


If your tree looks like the photo below, you had better get some more Tanglefoot on it.  This tree has lots of insects and I am sure that the leaves are because of a leaf blower.  One way to tell is that there is a lot of other smaller debris and leaf chips on the Tanglefoot.   I suggest that when the band is installed that the Tanglefoot be started on the lower portion of the tarpaper band so you can easily add to the band above the old Tanglefoot.



January 29, 2008 Tuesday

It is time to inspect those traps.

Things have picked up a great deal.  Today I found 202 female cankerworms on the main trap at my residence.  Also I installed a second trap in the back yard as an experiment.  I used the plastic tree wrap that looks like Saran Wrap and found it very easy to apply.  It took a fraction of the time to install as the tar paper did.  I also put a rather thin band of Tanglefoot on the trap and had to be careful that I did not rip the plastic material.

The greenish picture below shows that trap before I applied more Tanglefoot.  The picture directly below is the main tree in my front yard which shows the narrow band of Tanglefoot that is almost filled in some places with dead insects.  I need to apply a little more Tanglefoot above that band to stop the insects.  I actually caught one female cankerworm today that was above the band.

I have looked at a lot of traps around the neighborhood ,and many are overwhelmed with insects.  Quite a few other traps have very few insects.

First photo shows how the male cankerworms and the mashed females have just about filled up the band of  Tanglefoot.  I left a good bit of tar paper above the band so I could add more Tanglefoot.  That time has arrived, and I will need to add more Tanglefoot now and again in late March or early April.



 The Photo below show the back yard tree.  The original Tanglefoot band is only about two to three inches wide and the insects have filled it up.  I am sure some insects are escaping and going up the tree.  In fact if you look carefully       xx       below the two xxs you can see her.  In general, I think the band of Tanglefoot should be 6” wide and 1/4 inch thick.  Over the season, it still tends to dry out as you will see in the next photo.  (below).  Tanglefoot does not dry out as much on the Green Saran Wrap.


Below is a Photo of a tree with pipe insulation.  It has really absorbed the Tanglefoot.  The tar paper will also absorb the Tanglefoot but less so than the pipe insulation.  The band is also very narrow and to me this installation was just wasted effort. 


The last photo below shows a bug barrier trap that was working, but now ceases to do the job.  The trap was installed properly, but there is limited surface area for trapping the worms.  Since many trees seem to have minor infestations, this type of trap will work on those trees.  If there is an abundance of cankerworms, they will crawl over the insects and go up the outside of the trap.

I have seen these traps with a lot of leaves on the underside also where they were blow upward by a leaf blower.

The good news is that if you have a Bug Barrier trap that is being overwhelmed, you can take some Tanglefoot and place it on the outside exposed side of the trap and catch female cankerworms.

Here is a count of the cankerworms since January 21st.

January 22 =7,  Jan 23=8,  Jan 24= 171, Jan 25=50,  Jan 26= 67,  Jan 27=57,  Jan 28=123,  Jan 29=202,


Bug Barrier Trap totally full of insects.  They are climbing over the insects and moving up the outside of the trap.


January 21, 2008 Monday

I have done a little comparison from last season to this one.
At the same time last year we had a total of 5204 female cankerworms captured. 
On the 21st of this year, we have captured only 1394 insects.  That is a difference of 3810 insects.

We were about a month later getting the migration than last year and the counts are down every day as compared to last year.  In the fall of 2006, December had about 1500 insects and January approximately 3000 insects.

The overall timeframe for this migration is about 103 days, but it really slows down for a week or so at both ends of  the cycle.
Last year the bulk of the insects went up the trees in some quantity for some 63 days.  So far this year we have had 40 days overall and 32 days when have seen some evidence of insects but no where near the numbers as last year.

 Last year the there were three days with an exceptional number of insects 482,  506, 718.  This year the three highest numbers are 129, 289, and 361.

Below are the recent numbers. 

Monday Jan  14=22, Tuesday Jan 15=32, Wednesday Jan16=26, Thursday Jan 17=116 (snow in am), Friday Jan 18=49, Saturday Jan 19=23 (some wet snow and rain), Sunday Jan 20= 18 (very cold), Monday Jan 21= 7 (20 degrees F.)

January 14, 2008 Monday

The count on Saturday Jan  12 was 13 female cankerworms and Sunday Jan 13, was 361.  This is more like what I would suspect now that we are into days with about 45 to 50 degree highs.

I think tomorrow will also be a high count.  Weather prediction is that we will have rain later today.

January 11, 2008 Friday

This week has been strange.  The daily counts were down a lot.  

Jan 8 (tues.) = 58, Jan 9 (wed.) = 25,  Jan 10 (thurs) = 15, Jan 11 (fri)= 7

All around town the counts are down, however, there are a few area where there is a lot of activity.  The willow oaks between the tennis court and sugar creek in Freedom Park have lots of cankerworms.  As I have commented before if the band of Tanglefoot is too narrow, the worms will crawl over other stuck insects and go right up the tree.  In this case look at the female cankerworms that are visible above the band.  There is no telling how many have already crawled up the tree.  I could see about six insects at the time I took the photograph..   The yellow pen is aimed at one.  In this case there are both leaves and cankerworms filling the Tanglefoot.  The amount of Tanglefoot on the band is not wide enough.


While I am showing some photos, here are a few others.  This is a close up of stuck cankerworms but notice the eggs that are laid on the willow oak leaf.  I hear that the average egg mass will have about 200 eggs in it.  Normally, they are laid up in the tops of the trees but I counted close to 300 eggs a couple of years ago.  It was an egg mass laid on the tarpaper.



And Lastly,  Check out this double dogwood.    How is this supposed to work ?????    When I first saw this I thought somebody missed the boat.  However when I got around to photographing the tree, I looked under the wrap and sure enough there is lots of batting material crammed up in the void between the two trunks.  This shows one not to judge too hastily.



January 7, 2008 Monday

I think the very cold weather and a rainy day slow the worms up. I expected a lot of worms on Friday and Saturday and did not see many. Then on Sunday, it was like they were just waiting and standing in line to crawl up the tree.

Jan 5=2, Jan 6, (Sunday) = 289, Jan 7= 129.

It will be interesting to watch the next few days when it is supposed to be in the 70’s with some rain.

January 4, 2008

We have had enough cold, but the worms are very erratic. Lots of rain does slow them down, but it will be interesting to see what happens since we should have some warm days coming up.

Dec 29=5, Dec 30=0 (rainy day), Dec 31=0, Jan 1=63, Jan 2=25, Jan3=5, Jan 4=0

December 28, 2007

December 19, 2007  10 cw  total 21

December 18, 2007  4 cw  total 11 

It appears the cankerworms are finally on the move.  December 17th there was no activity.  Yesterday the 18th there were four cankerworms and today (Wednesday) my trap had ten female cankerworms in the Tanglefoot.   Last year I observed the first female cankerworm on November 16th, and the annual migration really picked up by the first of December.  We know that it takes a hard freeze to bring the cankerworms out.  Earlier this week when the temperature dropped down into the low 30’s for a couple of days seemed to do the job.  Check the graph posted on December 11th below to see what the cankerworms did some years ago.  The starting date which was not marked on the chart was about the November 25th.

Why is this important?  When these insects first started chewing on our trees we did not know what to expect.  Literature stated that a heavy infestation was 30 or 40 female cankerworms during the season.  We were getting over 8000 on one tree.   Defoliation for three years in a row plus the drought will do serious harm making the tree vulnerable to other ailments.  It is probable that we will see quite a few trees die this season.  It is too early to tell.

The purpose of logging this information daily was to see the time frame that the cankerworms needed to go up the trees and lay their eggs.  Also the number of insects is important because there are parts of town that unaffected and others where the trees have been clobbered for quite a few years.

In general the peak migration has been December 25th.  Expect it to be late this season.  Last year there were approximately 1500 insects captured in December and 3000 in January.

If you have not gotten bands up on your trees do it immediately.  The leaves are gone and each insect that gets up the tree can lay approximately 200 eggs.

Go back to the cankerworm report for other details.  Call me if you feel you need to 704-618-6214  jack mcneary

December 10, 2007  total 7 cw

December 16, 2007     new total

dec   15  3 new worms

We had about an inch of rain last night, the first in a long time.  There were three cankerworms on the trap on Saturday the 15th of December and one Sunday morning.  Below is a photo I took yesterday of one of the female cankerworms.  I took her from the trap before she got into the Tanglefoot and had her pose on a twig.


December 11, 2007, two cankerworms  total 4 cw

Still very little activity.  I have found 2 female cankerworms on one tree and one on another.  I do not expect to see the migration start until it cools down again.  To have it 80 degrees for two days in a row in December is really extreme.  For what it is worth, last year I captured one cankerworm on November 16th 2006 and a total of 26 for the month of November.  In December it was a different story in that I captured 1987 and in January 3901.  In February there were 27 insects trapped.   Later in the spring there were thousands trying to go up the tree and I estimated there were at lease 1000 insects on the tree.  Had those insects been allowed to go all the way up unimpeded, who knows how many others would have followed.

Below is a graph of the migration in 1997/98.  In general, the peak has been around Christmas.  This year I expect it to be later.  This chart was made after the migration.  At the time I did not know that we would have such a problem with the cankerworms.  I would have recorded the information more accurately.  Nevertheless, the peak number of insects on a single day was over 120 which is pretty significant.


December 8, 2007 one cankerworm  total 2 cw

Below is not a great picture of a cankerworm.  This was the second one for the year and has some Tanglefoot on her legs.  This should give you an idea of how big the insect is since the photo is taken with the insect on a Sharpie marking pen.




December 7. 2007

One of my neighbors said that he had about 20 cankerworms on his trap.  I went to look this morning at about 8:30 and did not find any.  I did find this insect which looks to me like a leaf hopper.  Note that it has red eyes.




December 6, 2007  1 cankerworm  total 1
I saw the first female cankerworm stuck in the trap on the big willow oak in my front yard early this morning. Every year the sunny side of the tree is the first place I notice cankerworms. Now with the recent wind most of the leaves are gone, and it is time to get the Tanglefoot on the traps. We are supposed to have some warm weather so that will make it easier to apply the Tanglefoot on the traps. It is sticky stuff so using disposable rubber gloves is a help.

I talked with Steve Ketner who is with the tree department of the city. The city is banding public trees in the major streets that are over 24 inches in diameter. That means that if you have smaller trees in your planting strip that you care about you will need to band them or hire someone to do that.

Make sure that you do not band trees that are not affected. (list of trees that cankerworms like)

Banding by the companies contracted by the city will begin early next week.

There are five companies that are banding 5700 trees for the city. The companies are as follows:

      1. Arborguard                     (Myers Park)
        Davey                             (Dilworth)
        Clark’s Tree Service       (Eastover)
        Neff Tree                        (Chantilly)
        Asplundh                         (West Side) (Wesley Heights)

      This is the beginning.