Update: still no positive Id but after reading up on borers in general it seems I will need to invest in a pesticide called dichlorvos for post treatment/to kill it in the vine and probably sevin for pre treatment.
It is more difficult without an id but seems most borers come from either beetles or moths and sevin seems to be good with those.
My work area is clean so no issue there; one of the downsides of having a mini-forest I guess.
Moving forward I suppose my options would be either to invest in netting to keep the bugs off my vines or to nuke them with pesticides every season.
Hmmm....it may be more cost effective to greenhouse grow my cuttings instead.
Only positives from it all is i get to learn with the natives so when I switch to varities I will already have a good system in place.
Then secondly I got to analyze the different media mixes I had and made a couple interesting observations.
1. in two of my pots I decided to replace rocks with styrofoam bits and they liked it. Every plant in that pot was seeking them.
2. Two of my pots I used a used a really high ratio of rocks in the mix and it changed the way grapes grew. Normally they do a tap root and a bunch of small seeking roots but in the rocky pot the roots grew thick!
Yea I hear ya on the science comment. One idea I just came up with is to use metal, residential screen just around the first 2 nodes instead of the whole plant which will be just as effective but way cheaper to do!