NPK ratio and acidity OF apples?

I have a huge and beautiful wild crab-apple tree near my house. It produces so many apples that nearly all of them fall to the ground and go to waste. I'd like to plant a few berry bushes under and around this tree, and I was wondering what kind of a fertilizer rotten apples makes. It would be great if the apples made the soil acidic, because I want to grow blueberries, but if not, I DO want to know what will grow there. Since the area already receives such an abundance of bad fruit, I'd like to know what the NPK ratio and acidity of rotten apples is. If anyone knows, please tell me!

Under the tree, there is already growing: poison ivy, wild parsnip, milkweed, wild raspberry, buck-thorn, diseased elm saplings, dandelions, and grass.

I'd like to keep the milkweed and wild raspberry, but the rest could do with a replacement.

I don't think blueberries would be the best choice to plant directly under the trees. They need consistently moist soil. I think the apples would be too much competition. I have black rasperries under a cherry tree. It works great. I think blackerries or strawberries might work too. I don't think the acidity from rotting apples will make much will make much difference. The apples may attract animals that will eat the other plants or other fruits though.

I would also graft some other good varieties of apples onto at least a few branches.

Good to know about the blueberries. I'll certainly plant some hardy cultivated raspberries, probably heirlooms, under the tree. And I already have some *ahem* escaped strawberries from an old garden experiment waiting to be transplanted. And I have a wet area somewhere else that I was saving for some willows... maybe blueberries will work there. Just gotta test the soil...

As for grafting, I honestly am intimidated by the idea. The tree is so big and beautiful and old. I would hate to see some sort of disease introduced... But it's a vigorous and healthy tree. It would probably be fine. And it would be nice to have some apples that are good for more things than jelly, even though the jelly DOES taste really good.

Right now we have a pair of pileated woodpeckers living in the tree. Every morning we look out and see them pecking at apples and feeding on the bugs in the sick elm tree nearby. And a herd of deer will walk through once in a while. Yes, I definitely feed the wildlife. It's a nice sight.

Do you think comfrey would provide a mutually beneficial relationship to both the apple tree and the raspberry and strawberry plants? I have rabbits...

I think my rasperries are Jewel. They're very disease resistant. I've had them for about 12 years.

I'm still learning grafting, but I've had some successes. I've mostly used an omega grafting tool. It makes matching the ends easy. You can't do a very big scion though. I think if your old tree is healthy, it's not likely to get disease from grafts. It is already a nice tree though so maybe you don't want to chance it. I think I'd try grafting some small branches just to learn how. Also you could graft apples with different ripening times and maybe cut back on the wasted fruit. I haven't tried that though. I'm planning to graft some Fameuse scions onto an old tree this spring.

I haven't tried comfrey yet. It's sounds pretty useful though.

I will look into Jewel raspberries. Maybe I can try grafting some edible apples onto one of the smaller apple trees on my property for practice. I have one that produces few apples each year; maybe I could test a more prolific apple variety...?

Thanks for the help!