Frankentree understock.....pitmaston vs Black Oxford

So, I want to have a B118 tree out front. I have a couple first-year grafts, but they are sticks. I also have 3 possible understocks, I am leaning towards using a 4-foot Pitmaston Pineapple or a similar size Black Oxford as the understock. I also have a Belle du Boskoop, possibly.

My issue (OK, I have a lot of issues, but in this case) is the oxford is supposed to make a nice, rugged, long-lived tree but it is prone to biennial bearing. If the spared Oxford branch goes biennial I could care less, but does anyone know if a biennial “trunk” impacts the limbs themselves?

OF the 3 any reason one stands out above the others?

Thanks in advance,

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I’m not sure this speaks to your question, but we have both Pitmaston and Black Oxford, and so far Pitmaston has been a good deal more vigorous. These are very young trees, and I don’t know whether my observation squares with your experience or the general tendency of the two varieties, but from what I’ve seen I would be inclined to use Pitmaston (or BduB) as an understock over Black Oxford.

i believe pitmaston has a reputation for light bearing, I suppose that should have been asked before too: would understock like pitmaston potentially diminish the rest of the tree’s bearing?

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Didn’t know that about Pitmaston, thanks for mentioning it.

I think you’re asking a really interesting question about whether understocks can influence the bearing habits of whatever you graft onto them (whether biennialism or light/heavy bearing)? I mean, rootstocks influence bearing, of course, but does that extend to understocks? Seems like something that would be valuable to know when constructing a multigraft.

Hopefully someone more knowledgeable than me will chime in!

For what it’s worth, I just took a look at the information provided by Orange Pippin and Keeper’s Nursery, and they both describe Pitmaston Pineapple as being a heavy bearer. Let’s hope that proves to be the case for both of us!

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I would go with a triploid, due to vigor, so Belle de Boskoop.

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I had been thinking boskoop before, and had taken it out of contention because I was thinking of sending it elsewhere, but maybe I should reconsider that move…

I don’t see an answer to this question … its no, biennialism is caused by over-bearing one year which is due to the spurs/flowers and not the trunk. Some people have claimed rootstock can affect biennial bearing but the scientific studies found it did not.


I wanted to revive this thread as I have a similar question - I have a bunch of apple cultivars on the way this spring as various bench grafts and scions. I am planning to graft the majority of them onto various crabapple and older unproductive trees I have access to at my parents place and my work office with the intention of adding a scion from each at my house once my trees get big enough. That being said, I want to make the right choice for which understocks to use. I am using m111 rootstock and plan to prune regularly to keep my trees closer to dwarf/semi dwarf size. I have Black Limbertwig, Grimes, Pitmaston Pineapple, Blue Pearmain, and Wolf River as benchgrafts. Scions will be Arkansas Black, Ashmead’s Kernal, Belle De Boskoop, Cox’s Orange Pippen, Empire, Gold Rush, Karmiijn De Sonnaville, Keepsake, King David, Liberty, Macoun, Rubinette, Stayman Winesap, Westfield Seek No Further, and William’s Pride. I Also have 10 M111 rootstocks to play with and may just try practicing grafting with them. Any thoughts on which would be best for a tiny yard and no/minimal spray regimen?

I will also mention I only plan to keep 1-3 trees at my house when it’s all said and done, just with lots of varieties on each tree.

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