This year I decided to do some cross-species pear grafts that I have read about.  The reason was to make miniature or highly dwarfed pear trees.   I have seen posts on various websites regarding compatibility, but it's hard to find much data.   Especially, I could not find cultivars that are named, as compatible with pear.

I used whip-and-tongue for each of my grafts.  If they took, I didn't need multiples, so I did a couple with a no-name Asian pear from my yard, and an Orca European pear from my yard.  I know that no-name aspect doesn't help a lot, but it is what I have available.

I bought the rootstock plants based on nursery descriptions of the plant size and what was available, and cost.  Those included

For Serviceberry, I bought the variety Thiessen (Amelanchier alnifolia) and Regent (Amelanchier alnifolia).

For Aronia, I bought the variety McKenzie (Aronia melanocarpa).

I bought two hawthorns - a ChineseHaw (Craetagus pinnatifida) Red Sun (because I grow that variety already and we like it) and a black Hawthorn (Craetagus douglassii). 

For apple, I bought scion for the variety Winter Banana, which several hobbyists describe as an apple that accepts pear scion.  I used Winter Banana as an interstem graft, either onto Bud-9 highly dwarfing rootstock, or onto a branch of an existing established multigraft tree, this branch being WineCrisp.

This was a challenging year for everyone, and more so for me due to health issues.  I was unable to care for some of my garden plants for a while, including these grafts.  I actually misplaced a couple of them, finding them when I cleared out a patch of snowpeas that had overgrown them.   However, there are a few results that I wanted to share.

Neither of the grafts onto Serviceberry grew.  The understocks did grow, so at least I have some Serviceberry plants to play with next year.

Of the Craetttagus, the Euro pear on Chinese Haw took and grew quite well.  The pear graft had about 2 feet of growth. 

Here is that graft.  It's a little uglier than my apple grafts onto apple, but the scion still seems happy.

The graft on Black Hawthorn did not take.   The Black Hawthorn plant grew nicely, so I might try again next year.

The graft on Aronia was Asian pear.  Interestingly, that was one of the ones buried under snow peas and other plants, wasn't watered all summer, and I just discovered it.  Despite all of that, it was alive and had about a foot of growth.

That leaves the grafts of Euro pear with Winter Banana apple interstem.  The one on Bud 9 did not take.  The Winter Banana did grow.  The one on the existing tree did take.  That only grew a few inches, whereas my graft with Winter Banana but no pear scion grew a couple of feet.

I don't know what any of this means as far as how they will do next year.  I certainly hope that other aspects of 2021 are better than 2020 has been, and I can continue to get into the garden and care for these.  My plan now is to replant the Aronia / Pear graft into a container where it will get more TLC.  I think I'll also cut the Winter Banana / Pear graft off and re-graft it onto a Bud - 9 or Geneva 222, whichever I have available, to see how it does with the healed and viable pear/apple graft.  One thing, I never took off the plastic strips, so there may be some constriction of the grafts.  That doesn't usually hurt anything.  I took them off today.

I hope this provides some information for others as far as potential compatibilities.  I don't know if these will lead to healthy mini or dwarf trees, or what the fruits will be like.  I read that there are some German amelanchier rootstocks for pears that work out pretty well for pear production and dwarfing, but I didn't know where to get them.  As for aronia, I read that the aronia stem stays small and the pear stem becomes larger - I don't know about the cultivar effects for that.  We'll see what happens.