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A couple of weeks ago I noticed tiny clear to opaque egg like things on the new stems of my grapevines. I took a pressure sprayer and hosed them all off and a few days ago I noticed they'r back again. I fear that using this method will miss too many now that the vines are getting fuller with many places to hide them.
Can anyone identify what kind of insect they might belong to and recommend how to best handle this invasion?
If you can't see the eggs well enough using this site, I can email you the pictures for a closer view.
Thank you so much for looking.
BT - Kurdistani is unlikely to ever develop resistant varieties. It works like swallowing razor blades as the "toxin's" rhomboid crystal structure slices open the guts of larvae that FEED on leaves containing the bacteria that contain the crystals and they digest themselves to death. Don't feed on my plants, don't die.
(All BT "toxin" works the same way but is highly species form specific. This limits its killing to a limited number of species and therefor has appeal).
It's biggest drawback is it takes 2-4 days of eating before die off. Heavy infestations can destroy crop or even the plant by then. BT is best applied at the beginning of the hatching.
I learned my lesson and when I found a new vine being hit just 3 days ago I applied spinosad (a "organic" neurotoxin) late in the day and all caterpillars were paralyzed and most unhappy the next morning. 1/3 of the leaves were left and the vine survived. Earlier this year several were not so lucky. While I do not particularly mind a certain amount of predation at some point if the infestation is heavy enough you either take drastic steps or lose your plants.
Spinosad will broadly kill larval forms but has the "advantage" (to me---others don't like it since it has no staying power, but I figure I've done my killing I don't need anything else to die that comes along later.) of breaking down rapidly in sunlight.
I know of no natural predators to skeletinizers---even the adults are toxic. Believe me I wish I did.
Alright there are 2 identified predators: Ametadoria misella (Sturmia harrisinae) a tachinid fly parasite that lays its eggs in 4th stage Harrisina brillians larvae and Apanteles harrisinae, a tiny parasitic wasp that prefers laying eggs in the 1st stage larvae. Sure would be nice to find something that likes to devour skeletinizer's eggs.
Thank you for all the great info. The "eggs" in the picture did actually turn out to be sugar drops. They were random in placement and size. However, I do get the skeletonizer worms. I think I will get some spinosad. Do you have a local source or is it available online? I have until next Spring before I need to use it.
On the other hand, my vines were hit hard by white fly followed by a heavy infestation of leaf hoppers. Usually this time of year the vines are green and growing but they are both either dead or dormant looking already. I got some white fly sticky traps that work for leaf hoppers too but it was too late. I plan on spraying the vines really good before they set fruit next year and nip all this in the bud. LOL
I got really bad leafhoppers this year, too, and my vines look awful. I forgot about the sticky traps, might have to give them a try.
Honestly, these do not look like eggs to me. They are not uniform in size.
Looks like sugar drops, like the vine is weeping moisture out and it is drying.
Leafhoppers lay on the undersides of leaves, see this link: Bug Guide
Your vines look good and healthy, and so I would watch and see if you can see anything come out of these things. Plants are designed to take a bit of bug abuse ;)
Wow, I never heard of that, nor have I ever seen it before on my grapes. They are only on the thicker faster growing stems and there are none on the leaves. Naturally I jumped to offensive critters since they suddenly appeared and I had that infestation of skeletanizers a couple of years ago but never saw the eggs, just the worms after they hatched.
I'll keep my eye on these to see what happens. I did hose them off again yesterday and there are more again today.
Also, there are a few tiny white things flying around the vines when I am inspecting them and that's why I thought they might be leaf hoppers. I've never heard of them before either. Boy am I naive. LOL
In the Bordeaux region of France, it's called "Les Vignes Pleurent" , The Vines Cry. Also in the spring after sap seeps out from the pruning cuts. The tiny white things could be whitefly, nasty little bugs.Managing Whitefly
Well, after watching these things for a few days, I'm going along with Gerry on the "grape pearl" idea. They just seem to dry up, but also new ones pop out.
I too think the little white things are white fly, just a few right now. I did also find some eggs yesterday on the back of a leaf so figure I might as well give a light spraying of Bt and nip the problem in the bud, especially since there are much few leaves to spray right now than there will be later.
Thank you! I've been searching the internet to identify these pretty little pearls. They just didn't seem threatening to me.
Very cool Gerry. Learned something new and I am pretty sure I spotted these on my neighbor's mature vines. I too have been keeping an eye on them ot see what emerges. Now I won't be puzzled if nothing comes out.