Emerald ash borer update

Have you noticed all those purple sticky traps?

Emerald ash borer sticky trap

Emerald ash borer sticky trap

The PA Department of Agriculture has hung them in ash trees all over eastern PA this summer.  My guess is we’re going to find out about a considerable range increase for this terribly destructive insect.  Already this year, 2 new counties have been added to the list, Huntingdon and Wyoming.  IT IS NOW IN THE EASTERN PART OF PA, having been detected just north of Wilkes-Barre.

Things you need to know: – Adults can fly on their own approx. 1/2 mile.  So the pest isn’t moving very fast on its own.

– It gets help in colonizing territory from people moving infested firewood.

– If emerald ash borer gets close to your area, your landscape trees can be treated by soil injections.  Bigger trees can only, so far, be successfully treated by trunk injection of insecticides.  Treatments need to be done annually to be effective.

– Experts do not suggest treating trees unless an infestation has been detected within 15 miles.  To treat before the threat is there is a waste of money.  And trunk injection is an invasive procedure.  Don’t injure the tree with it until you need to.  And don’t believe anyone who tells you that their trunk injection method causes no injury to the tree.

– If your trees are monitored by a competent arborist, you are not likely to be caught by surprise by emerald ash borer.  If it    shows up, you will have time to control it if you choose to.

NEW information: A new chemical is available that is highly effective and lasts more than one season.  Hopefully it will be  legally registered for emerald ash borer control in Pennsylvania soon.  And hopefully the price will come down (it’s very expensive).

MORE NEW information: A new monitoring tool may soon become available.  Recent research on developing a sex attractant (pheromone) has been promising.  The purple monitoring traps now use two aromatic tree oils as attractant.

Still more new information: Research has also uncovered promising indications of natural biological control of emerald ash borer.
We in southeast PA are lucky to have the benefit of a decade of other’s experience and research before having to face the emerald ash borer.

Bagworms and Bagworm Predators

This morning we did a pest monitoring visit for a good client, a 250unit townhouse complex.  Historically the worst pest here (invertebrate that is) has been the bagworm, because of the preponderance of arborvitae and juniper in the landscape.

A big problem with bagworms is that to the untrained eye they are not easily seen, so they’re often not noticed until late summer when they are no longer easy, or possible, to control, and the tree has been killed or severely damaged.

But early instar (young) larvae are EASILY controlled, you just need to know when and how to spot them.

juniper bagworm

cocoon of bagworm larva

Cocoon of early instar larva. Can you see it? The caterpillar has camouflaged itself by attaching juniper needles to the cocoon!

 We examined all the important host plants today, and only found one very small bagworm outbreak (thus the lousy photo-not a lot of subjects from which to choose.)

But what we DID find was lots of assassin bugs!  That’s a good thing!  They’re a predatory insect – one of the few predators of bagworm.

assassin bugs

assassin bug

assassin bug

Assassin bugs

The bagworm larva’s cocoon protects it from most predators, but the assassin bug can attack it successfully because it has a long, pointy mouth part (rostrum) that it can insert right into the cocoon.


See the rostrum? It’s the reddish brown spike curving down and rearward from the head

Anyway, the point of this story is that this clients landscape has very few pest problems.  And it is because they DON’T use regularly scheduled pesticide cover sprays.  When we encounter a pest problem that reaches a threshold requiring an intervention we just target the actual pest population, we don’t blast the whole landscape with pesticides.  And we use a control measure that can do the job with the least  impact on non-target species.  Bagworm can be easily controlled with Bt if caught in time.  Bt only kills Lepidoptera, no other insects.

So natural predators control almost all the pests for this client.  The bagworms rarely get out of hand anymore.  There are never any mite problems on the spruces or arborvitae or junipers.  This job is really easy if you know what you’re doing.

More insect eaters we saw today:

Damsel fly

Damsel fly

Predator mite (eating an earwig)

Predator mite (eating an earwig)

 Unfortunately a lot of companies still manage pests with regular sprays, whether needed or not.  This is stupid.  It’s like bombing the hell out of an entire country just to try to get one terrorist bad guy when you don’t even know if he’s there or not!  It’s a huge waste of money and ammunition, there’s loads of unnecessary collateral damage, and a lot of the casualties turn out to have been your allies!

The lesson : diagnose before you treat.  (treatment without diagnosis is malpractice)  Monitoring plants is the first and most important step.  It is the key element in an IPM (integrated pest management) or PHC (plant health care) program.

Another “Emerald Ash Borer” Scare

I was called to the clients’ home because her beloved huge white ash was not looking healthy- lots of dead wood- and had been receiving a hammering from wood peckers.  When I checked the tree, besides the woodpecker holes, I observed many exit holes in the bark that had been produced by boring insects.  Some were the typical oval shape of the ash-lilac borer, but some had that dreaded “D” shape that could possibly indicate EMERALD ASH BORER.

Sure looks similar to E.A.B!

I looked closer, picking away at some of the dead bark and poking into the borer holes.  Eventually I found, to my relief (and the tree owner, Anna’s!), the wing cover of an adult ash- lilac borer in one of the “D” shaped holes.  False Alarm!! Not EAB!


The client REALLY wanted to save the tree, but I didn’t want to waster her money on an expensive pruning job if it were doomed anyway because of Emerald Ash Borer.  So my men climbed the tree and checked the dead branches, also, for signs of E.A.B. infestation.  All clear.  We went ahead with the pruning.  The tree is not in the greatest health but it’s now a lot safer without all those dead branches above the driveway and patio.  And it looks nicer too, don’t you think?




Emerald Ash Borer found in Kentucky

Last week the office of the State Entomologist in Kentucky confirmed reports of this devastating invasive insect in Shelby and Jessamine Counties.

Emerald ash borer was introduced to the US from China by way of imported wood products.  Since its discovery in 2002 it has spread rapidly, and will probably continue to do so.

Emerald ash borer was detected in Pennsylvania in the westernmost part of the state in 2007, and hasn’t been found farther east until just this past February (2009) when it showed up in Mifflin County (in the middle of PA) so learn what to look for if you have ash trees – apparently there is no stopping it from eventually reaching us.  More info at http://ento.psu.edu/extension/trees-shrubs/emerald-ash-borer.


The beautiful weather of this weekend will surely kick off our spring busy season.  I can’t wait, it’s been a long winter!

The Virginia bluebells in front of my office window are now in full bloom.

The Virginia bluebells in front of my office window are now in full bloom.

Note the spring beauties and a few dandelion in the lawn in foreground :mine’s not the typical suburban sprayed sterile lawn.

Today I saw the first blossom in my strawberry patch.  Spring’s definitely here.

Also today, in my driveway, I spotted this beautiful emerald green beetle.

THIS IS NOT THE DREADED EMERALD ASH BORER!  (the adult EAB does not emerge for another two months).  And, thankfully, they still have not been found here in Montgomery County, although they are in western PA.

The webs of eastern tent caterpillar are starting to become noticeable on the native cherries in the woods, as well as on the crabapple in my nursery.

I get a lot of calls about ETC, (with people often confusing it with other more destructive pests such as gypsy moth).  Don’t let them worry you – they are not going to invade like some of the introduced pests and populations are kept in check by natural enemies such as assassin bugs, parasites and birds. (it’s a favorite food of the Baltimore oriole)  I’m not going to spray the ones in my nursery, I’ll probably just destroy the nests before they eat a lot of leaves.


If I’d noticed this egg mass – the things that look like a swollen area on the twig – over the winter, I could have just pulled it off then and prevented its hatch.

Exciting things are happening outdoors every day, and at an especially fast pace at this time of year.  I’m going to try to keep you updated with regular posts here on this site, hopefully with some links to more information on some of the topics.