Asp a.k.a. puss caterpillars

These have been a hot news item lately in Central Texas.  I did a news interview & Facebook Live broadcast yesterday to talk about them.

While these teardrop shaped caterpillars look soft and touchable, they are NOT! Asps have spines attached to venom glands that can lead to a nasty sting, rash, and other issues. Some people may have a more severe reaction than others and where you are stung (thickness of the skin) can effect things. You can read my previous post on asps HERE.

KVUE story here:
http://www.kvue.com/news/fact-vs-fiction-the-asp-caterpillar/484727108

My technical skills are lacking, so I have no idea how to share the Facebook Live video outside of Facebook, but if you want to see it you can go to KVUE's Facebook page to find it.

Caterpillars- buck moth caterpillar, cankerworms and tent caterpillars

Cankerworm

The insects seemingly have arrived in our demogarden the past week.  I was out there with Master gardeners this morning and there was a lot to see....it makes me EXCITED (the Master Gardeners, not so much, as many of the insects are eating the plants they are tending so carefully).

So two items have already been covered recently in blog posts written by Dr. Mike Merchant in Dallas, so I'm going to direct to those pages and you can get all your information there.

Tent caterpillar

First are the tent caterpillars.  I had my neighbor find one last weekend and she sent me a picture for identification.  Mike's post on tent caterpillars.

Secondly, would be the cankerworms.  If you have oak trees in your area (and this is Texas, so who doesn't have oak trees, right?) then you probably have seen these or at least evidence of their activity.  Have you seen the silken threads hanging down from trees?  If so, then you have seen webbing from cankerworms.  Again, Mike has a great post on cankerworms here.

The last thing I want to cover is a caterpillar you DO NOT want to pick up.  This caterpillar has branching spines that can deliver a sting if touched.



Buck moth caterpillar

Buck moth caterpillars typically have a background color that is dark, but they can have varying coloration so some can be very light.  The body has white spots and the spines are double branched and form multiple rows along the body.  They can be almost 2 1/2 inches when fully grown.

Buck moth larvae are gregarious and will group together for the first three instars (smaller caterpillar stages).  After the third instar, they will wander off from the other caterpillars to feed on other plants until it is time to pupate.  And remember above how I was talking about oaks in Texas?  Well, that is the preferred food of buck moth caterpillars.

The adult buck moths are quite pretty and have a wingspan of 2-3 inches.  Wings are blackish in color with a white stripe running through the center with dark eyespots. Females have a solid black body while males have a black body with the tip of the abdomen being reddish-orange.

As mentioned previously, you DO NOT want to pick up the buck moth caterpillars.  The branching, urticating spines can deliver a sting when touched.  Reaction from the sting can vary but may include immediate pain, itching, swelling and redness.

 

Asp caterpillars

I've been hearing reports of people being stung by asps (puss caterpillars).  The larva is the problematic stage for this insect as the caterpillars often fall out of trees and land on unsuspecting people below.  When this happens, the person may get stung.

Image from hortipm.tamu.edu

The caterpillar has venomous spines which can cause a varying reaction.  There are some people who react more severely to the toxin than others.  The severity of the sting can also depend upon the thickness of the skin where the sting occurs.  Often stings will cause localized burning and redness (usually in the shape of the caterpillar) sometimes paired with swelling.  More severe reactions may cause fever, headache, nausea, vomiting and other symptoms.  If you are stung by a caterpillar and are concerned with your symptoms, seek medical attention.

Smaller instars are yellow in color while later instars turn pale green to white.  The spines containing venom are concealed in later instars by long, soft-looking setae (hairs).

Asps are know to feed on foliage of over 40 genera of plants.  They will often wander to nearby plants when the are preparing to pupate.

If you have large populations of these caterpillars and would like to manage them, you can try Bacillus thuringiensis var. kurstaki (this targets caterpillars only, but will also kill "good" caterpillars).  You may also look for active ingredients such as spinosad or azadirachtin (both naturally-derived products).  These products tend to work best on smaller instars.  Another option would be a residual pesticide labeled for caterpillars that is okay to use on plants.