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Grape Leaf Skeletonizer (Harrisina americana)

Order: Lepidoptera (le-pid-OP-ter-a) (Info)
Family: Zygaenidae
Genus: Harrisina (har-RIS-in-a) (Info)
Species: americana (a-mer-ih-KAY-na) (Info)


This bug has been reportedly found in the following regions:

Apache Junction, Arizona
Chandler, Arizona
Glendale, Arizona
Globe, Arizona
Tempe, Arizona
Tucson, Arizona (2 reports)
Barling, Arkansas
Rosedale, California
Sarasota, Florida
Benton, Kentucky
Thibodaux, Louisiana
Las Vegas, Nevada (3 reports)
Glouster, Ohio
Johnson City, Tennessee
Show all

Members' Notes:


On Oct 20, 2016, azmarymary from Tucson, AZ wrote:

I had the caterpillar infestation but after several applications of BT, I finally got rid of them. After severe damage, I'm finally getting new growth. Should I still cut them down? This is their 1st year.


On Sep 29, 2016, Truth12345 from Rosedale, CA wrote:

Just wanted to say that these little bugs came on fast but thankfully after harvest here in SoCal. I plan on cutting them down and hopefully that will end the infestation.


On Aug 19, 2014, VineLand from Thibodaux, LA wrote:

I "had" a grapevine growing on a trellis that is also home to a trumpet vine. I noticed the grape leaves becoming laced & "skeletonized", turning brown & dying. After searching on this site, I went out to look. Eeee-Gads!!! There were thousands of these little yellow striped caterpillars on the leaves ... & tons of black-pepper-sized eggs scattered about. I cut the vine immediately, where the main trunk comes out of the ground. I'm hoping beyond hope that the little f**kers won't like eating dead leaves, & eventually die off. Fortunately, it seems as though trumpet vine foliage are not to their liking.


On Jun 12, 2011, frogymon from Lisle, IL (Zone 5a) wrote:

Had a real problem with them this year and couldn't find Bt locally, so wound up cutting off worst infected leaves and squishing the rest of the caterpillars by hand. Haven't seen any since it the weather has been consistently in the 90's.


On May 30, 2011, cfusion1 from Las Vegas, NV wrote:

Yes DT is the only method of purchased pest control you can use. The eggs are black pin dots like someone took a pen and inked all your leaves. I have had them two years in a row now (grapes vines are three years old) and this year I am not spraying with DT. There is a non pesticide removal process and it is labor intensive but worth it. In the cool of the morning and evening venture outside and check for the flying blue/black moth. Either spray it to the ground with a strong blast of water or swat it with a fly swatter and kill them as you see them. You will not see all of them, but you will cut down on how many lay eggs. Next look under the leaves of your grapevines for the black dots and rub them out with your gloved fingers. If you miss them and the caterpillars are eating remove the i... read more


On Jun 15, 2009, McihVegas from Las Vegas, NV wrote:

We had to cut down the foliage of our grapevine that was 12+ years old. Does the vine survive this catapillar?


On May 24, 2009, daveclancfamily from Apache Junction, AZ wrote:

a week ago my grapevine was full and beautiful, today there is not one leaf left! I have hundreds of catapillars on there, but i just noticed thousands and thousands of these black dots on the wall next to it. are these eggs?

Is Bt the only killer to use? I really want this infestion gone.


On Jun 27, 2007, daltonreed from Glendale, AZ wrote:

Glendale, AZ June, 2007: I believe we have this same pest as well. We tried the dishsoap and water but now the leaves are being taken over. Any suggestions on how to get rid of them please email me.

[email protected]


On Jun 12, 2007, ylwbrd from Chandler, AZ (Zone 9a) wrote:

I have had a Thompson grape vine in my yard for 9 years, and have never had a problem. This year I noticed damage to leaves, and upon closer inspection found the little critters, lined up in circles, devouring the leaves. Some were no more than the diameter or a pin, and others were more mature and about 1/4 in dia. and about 1 inch long. First I sprayed with an organic soap, and had no results. When the BT finally arrived (my local garden centers didn't know what I was talking about), I sprayed, but by then most of the caterpillars were gone. Now my yard is full of the flying insects. Pretty, but I know they will lay eggs and we're off and running for next season.

Does anyone know about what else these guys are hungry for? Do the adults cause damage? Are there any natural p... read more


On Apr 25, 2007, Marielouise2 from Tucson, AZ wrote:

These are very destructive pests. At first sign of caterpillars, treat with Bt (bacillus thuringiensis). Caterpillars must ingest the spray; shortly after eating it, they stop feeding and die. This is a biological control and is not harmful to birds or beneficial insects. Bt is available at garden centers.

The caterpillar hairs are irritating to the skin.


On Jul 30, 2006, melody from Benton, KY (Zone 7a) wrote:

The yellow caterpillar eats grape foliage, sometimes several lining up and eating side by side to devour a whole leaf.

Found throughout the eastern half of the US, the adult moth has a wingspan of around 1".

It gets it's name from the trait that the very young caterpillars have of only eating the foliage between the leaf veins, thus the skeleton look. As the caterpillars mature, they aren't as choosy.