Friday, May 30, 2014

Emerald Ash Borer- be on the watch

The Emerald ash borer is currently NOT found in Texas.  It has recently been reported in Nebraska and Colorado, so Texans should be looking for it.  If you suspect that you have these insects, collect samples of the insects and submit them to me or your local Extension Entomologist.

Image from www.emeraldashborer.info

Emerald ash borers are small (less than the diameter of a penny), elongated, metallic green beetles. Antennal segments 1-3 are cylindrical while segments 4-11 are serrate (triangular or saw-like). These beetles ONLY attack ash trees and can kill a tree within 3-5 years.

Emerald ash borers were accidentally introduced into the United States in the 1990's, but wasn't discovered to be the source of ash tree death until 2002.  They can be easily moved in ash logs and firewood.  There are more tips on how to identify here.

You can find signs and symptoms of infestation here.  

Information on Emerald Ash Borer can be found here.  Texas information on Emerald ash borer (including reporting information) can be found here.

Friday, May 16, 2014

Fire Ant Webinar- FREE!

Guess who is up next month for the All Bugs Good and Bad Webinar Series?  That's right ladies and gentlemen, it's me. So if you haven't heard me talk fire ants previously or want a refresher course, log on.

Here's the skinny:

All Bugs Good and Bad Webinar Series: Fire Ant Management

Learn how to manage your fire ant problem in this webinar by Wizzie Brown (this page has an awful, old picture of me...MUST get it updated soon!), Program Specialist - IPM, Texas A&M AgriLife Extension. You don't have to spend a lot of time and money to control fire ants.  A little knowledge about how fire ants live will make you see how easy it is to control them.  Moderated by Mike McQueen, Regional Extension Agent, Alabama Cooperative Extension System and Amanda Tedrow, County Extension Agent, University of Georgia Cooperative Extension. Click here to login as a guest and participate in the live event.  For more webinars in this series, see All Bugs Good and Bad 2014 Webinar Series. The webinars are brought to you by the following eXtension Communities of Practice: Imported Fire Ants, Urban IPM, Bee Health and Invasive Species; and by the Alabama Cooperative Extension System.
 

The webinar will be held on Friday, June 6, 2014 at 1PM CDT.  You can login for the webinar here.

Remember, the webinars are FREE and they will be recorded so if you miss it then you can watch it later.

Wednesday, May 14, 2014

Juniper budworm & Spider mites

I've had a few people contact me late last week about their juniper trees (sometimes called cedar trees) turning brown and needles dropping off.  I was able to get a sample sent in from the Liberty Hill area and found webbing along with spider mites.  About 10 minutes after looking at the sample, I got an email from Pat Porter about another problem case with junipers in Central Texas, but this time the culprit was the juniper budworm and was in the Bee Caves area.



Juniper budworm. Photo by Steve Darnell.
You can find more information on spider mites here.

As for the juniper budworm, the caterpillar is the damaging stage.  It is small to medium in size (depending on the instar) and green with a brown head capsule.  The caterpillars, or larvae, feed on juniper foliage and construct silken tubes where they are protected.  The tube is also where the insect pupates.  Adults are small brown moths in the family Tortricidae (also known as leafrollers).

Branch with juniper budworm. Photo by Steve Darnell.
If trees are prized landscape trees that provide screening or shade, then control may be warranted.  For management without chemicals, try handpicking the infested branch tips.  You can place them in a bucket of soapy water or double bag them and throw them in the garbage.

There are natural controls by beneficials (birds, wasps, flies, etc.) that help to mange these insects, so if you choose a chemical control method, choose wisely.  You can target caterpillars only by using Bacillus thuringiensis var. kurstaki.  Other less-toxic active ingredients include spinosad or azadirachtin.  Other possible active ingredients include things such as lambda-cyhalothrin, imidacloprid, carbaryl or acephate.



Friday, May 2, 2014

Webworms and a garden visitor

Webworm caterpillar.
This week-- tomorrow (May 3, 2014)- is the Travis County Inside Austin Gardens Tour.  The AgriLife Extension Demonstration garden is on the tour so our Master Gardener group has been working diligently to get things in top condition (and the garden looks great!).  A group was here on Tuesday and they asked me to come out into the garden to give a quick bug talk.  After we went on a field trip across the street to see a harvester ant colony and a leaf cutting ant colony I headed back to my desk.  Fortunately, a volunteer came in and asked me back outside to see what they found.

Webworm webbing.
In one of the trees, they had discovered webworms (see below for more information on webworms).  Not only were there webworms, but there was a Texas Spiny lizard sitting on top of one of the webs eating the caterpillars.  It was so incredibly cute!

The lizard after its meal.
Webworms are caterpillars that defoliate trees and cause large, unsightly webs on the tips of tree branches.  There are 2-4 generations of webworms that occur each year.  The first generation appears now and the last generation occurs in late fall.  The last generation tends to be the most damaging.

Webworm larvae, or caterpillars, are about an inch long when fully grown.  They are pale green to yellow with tufts of long hairs projecting from their body.  Most people notice webbing that they create on branches.  Webworms feed with in the webbing and use it as protection from predators.  When the caterpillars need new foliage to feed on, hey expand the web.

To manage webworms, try the following:
  • prune eggs masses off before the caterpillars emerge (egg masses are on the underside of leaves and are covered with hairs from the adult moth)
  • prune out small webs when they begin to form in the spring
  • knock webs out of the tree with a stick or a high pressure jet of water; you can also open the webs with a stick or water to allow predators into the web
  • look for products with active ingredients such as Bacillus thuringiensis var. kurstaki, spinosad, azadirachtin
    • even when using a pesticide, you first must open the web to get the pesticide to where the caterpillars are located