Joining apple to apple or pear to pear could be done. It won't affect fruit quality. Pear to apple will be a short term union if it takes at all. Even if grafted together it again won't affect the fruit of either.

If you graft the tip of one apple branch to another you'll get upright shoots growing from the high point. Sap won't flow backwards at least not very far. It will go up to a watersprout.

FN

Would the fruit on the watersprout be affected?.

M

No, fruit will be the same as the original wood that the sprout grows from. Most fruit trees are grown on a rootstock. That can have some affects on the fruit such as size and maturity date. But an apricot grown on a Lovell peach rootstock will still be an apricot.

FN,

So basically you are saying that I should not expect anything interesting.

Mike

There can be changes to fruit. One most extreme case is mung bean grafted to tomato. Most mung bean grafts failed but the ones that grew would develop beans 30% heavier than the same group only on their own root. Then these grafted mung beans were crossed and found to have the same heavier beans in the next generations growing only on their own roots.

In the case of fruit trees I have read about pissardi red leafed plum grafted on apricot seedling roots. After several years the plum was cut down forcing up root shoots that imitated leaf color, shape and a few other things similar to the plum.

You can expect some ugly graft unions between apple and pear. Some will take and may be long-lived, but most will probably survive for 1-3 years before being rejected.

While you are out there doing the "mad scientist" plant games, you may also want to throw in another idea. Approach grafts. If one tree variety was vastly superior over it's neighbor, as the preferred tree's branches violated the air space of the inferior tree's branches, you could shave, fasten, and tape up several intersecting branches during growing season. After several months of the graft area growing together, the "bad" tree's branch that extended downstream from the now-healed graft area can be clipped off. That way the "bad" tree can be used to further boost the "good" tree's growth and fruit production. Like splicing a second 8 cylinder truck engine next to your truck to boost it. As opposed to topworking the "bad" tree with separate scions from the "good" tree........I did this to convert 3 sizeable inferior muscadine vines that were along a fence and grew for years next to a much better vine. Each year I used the good vines' additional sideways growth to approach graft each neighboring plant's vines until over three years the good plant's vines reached all the way down the fence line to all three inferior plants. I clipped off all the unwanted growth from the three, so now all 4 large vines are making the good grapes. Other inferior muscadines w/o a good nextdoor neighbor to approach graft with instead got cleft grafted on top to convert them and made fruit in the second year following the cleft grafts.

Coping*.*,
That is a very interesting idea that I have to keep in mind. Most of my trees are going into their 3rd and 4th year in the ground and this coming year was the first year that I was allowing the trees to keep more of the fruit to maturity. I now have 65-70 trees ( apples, pears, peach/nect, apricot/pluot/aprium & cherries.) No two are of the same variety. I planted them all based on description and opinions of others. The only criteria for apples & pears was that I wanted varieties that I could NOT find at the local A&P.

So... I am sure that some will not live up to expectations and the idea of the "creeping topworking" is interesting as many have expanded into their neighbor's space.

Based on the feedback from all, I should not expect any dramatic results, but the proposed experiment DID produce a great idea..... yours. I was beginning to plan on what to do with those varieties that did not do well or did not live up to expectations or if I want more of one variety than another .

Thanx
Mike