Wasps and small bugs on an almond tree

Here in Greece we have an almond tree with a strange wasp activity going on for weeks now. The branches of some parts of the tree are densely covered with mottled brown bugs about 3mm long. The wasps do not eat them but are doing something with them and then eating a dark substance that falls on the ground below. I suspect it's a symbiotic relationship or perhaps the wasps are farming the bugs for a substance they produce, rather like ants do with aphids. I have searched on line and found nothing. Can anyone on here explain what's going on?

 

I'm wondering if it is some kind of scale insect?
They produce a sticky substance that wasps might well be interested in at this time of the year.

 

I googled them, they don't look very similar and effect leaves mainly whereas these bugs are on the bark. Thanks all the same for your input

 

Can you get a close up of the actual insect, I've tried to blow it up but it just becomes pixelated.

 

There's nothing worse than a pixelated bug They look more like black aphids to me..the sort you get on cherry trees, which are Prunus species too. Wasps do eat aphids, but they are probably also attracted to the honeydew that the aphids excrete. Anything sweet is a magnet to them at this time of year.....

 

Oops, some got squished. They look like aphids I guess, strange that they are on the bark not on the leaves, so I don't understand what they are eating from the tree.

 

At a guess could be Bark beetles and the wasps may well be parasitic wasps - using them as hosts :(
the honeydew seepage is maybe just an added bonus - this link is an Insect/beetle aphid id site -Aphid identification to genera
If it were me, I would be inclined to send these photos to them for their records, there is a contact form on site - New species crossing boundaries are becoming more frequent and im sure they would be the best people to contact ....also if there is anything untypical then they would be made aware of the situation, and you will have an answer regarding the long-term welfare of the Tree- Hope this helps in some way - Good luck

 

Hello. That's an interesting site and I will be emailing them. I believe they are aphids rather than beetles as they have no armor shell. It's the wasp involvement that fascinates me and I can't work out who is being exploited here, tree or aphid. I like the wasps, good army for parasites, tree seems ok, aphids seem to move about from branch to branch, they don't fly though. All going on just by my door, nature is wonderful.

 

Hello again, Would the aphids be laying eggs in the bark of the tree to overwinter, do you think?

 

hi, i don't know really. Wood seems really hard for lil aphids though