Save this benchgraft?

This variety is a California bred tree on a bench graft. Last year it spent the summer w/powdery mildew and 6 pairs of leaves. It stays this yellow color regardless of what I’ve done. It most likely would not ripen here except in storage and I could use the space. Save or discard?

Chikn, it sounds like you’ve already decided that you would be better off using the space for something else than putting more time and fuss into this one. Unless you have a strong emotional attachment to this one, I say use the space for something that makes you happy instead of something that sulks and complains for attention every time you look at it.

I have several California-bred apples and while they are usually busts for fruit quality in my climate I have not noticed problems with powdery mildew or general tree growth. But there are a few varieties highly susceptible and maybe you have one there. What is the variety?

I give benchgrafts a two strikes and out rule. If by the end of the second year they havent put on significant growth and look healthy they are getting yanked. Some grafts are just not destined for great things. IMO if it looks like the one you have pictured by the end of the 2nd growing seaon it is replaced.

Rather than yanking it, why not give it this season to see if it adjusts and if not regraft next spring. I have a tree here that never bloomed or flowered (plum) and always had light colored growth. It certainly was not a result of inadequate nitrogen availability I don’t know what it’s issue was/is.
I grafted it over this year and surprisingly the new graft seems to be growing the same way. Maybe a rootstock issue, maybe the planting area was the site of a spill or something long ago. Could be a rootstock issue or maybe the planting area is no good due to something in the soil.
I’m sure you are aware of this chikn, but sulfur will totally eliminate your Powdery Mildew issues.

Christmas Pink. Both benchgrafts of that variety had mildew badly. The other died. Rubiayat and Venus have done very well and should bloom next year.

Soil or spray, I have a 90% water dispersible granule that I use on blueberries. I could spray that.

Spray. Micronized sulfur sprays really well. I haven’t seen WDG sulfur before, but I’m sure it works well.