Blenheims are famous for canker around here, and I wouldn't plant nor graft any Blenheims. So you could have a reservoir of canker on the stock. But I am not sure if it would be the same in your case. Over here, the Blenheims rarely every bear crops. All pluots that I have experimented on are vigorous on apricots, much more so with Apriums that they seem to take over the apricot that you gaft them to. Japanese plums (aka Asian) will also be just right on Apricots (not too vigorous as pluots or apriums would be). Actually the Asian plums were called Japanese plums, and the Japanese plums did not really originate from Japan but from China. As credit to the Japanese, they were the ones who worked hard to improve most of the plums that originally came from China, so the world has known them to be Japanese plums. Now to prevent confusion between origins from China or Japan, we simply call them Asian plums. The European plums, excepting for very few types, are usually poor growers or incompatible on my apricots. I will be experimenting with Nanking Cherry if I can do a lot of prunus cultivar grafts on it. I love its small stature. If you really want many species grafted successfully together on one tree, I would rely on using apriums as the stock or interstem. These interstems first grows upright after grafting and so easy to position and receive various grafts on a tree without them crossing over, minimizing competition and agressive pruning to keep the grafted cultivars balanced.

Comparing apples and stonefruits is not necessarily valid. With self-fertile peaches/apricots and the like, there's a better than 75% likelihood that fruit from seed-grown plants will be all but indistinguishable from the fruit the seed was extracted from. If it's a 'landrace' type - like the 'Indian Blood' peaches - fruit quality of probably greater than 90% of seedlings is comparable to that of the original. Not so for apples(grapes, I have no idea). But, you'd have to grow that seedling through its extended juvenile period to reach fruiting age - and grafting/budding with wood from a bearing-age tree will cut that wait-time in less than half. Your seedling apricot would, however make a fine standard rootstock to topwork to a known superior fruiting variety, but it won't be the same as the rootstock selection your grafted variety is on.

Thanks to you all for all the good advice. I was leaning towards Citation until I read Someguy's comments on the wet soil. It is almost unavoidable that this tree will get considerable irrigation. So now I think Marianna 2624 might be the better choice. (Fowler Nurseries has an excellent page on apricot rootstock. http://www.fowlernurseries.com/Rootstocks.htm#Almond) If I stick with that choice then I'm left with the decision of cultivar -much easier, we are likely to love them all. I'll avoid Harcot (not a good canner, important to me). And I'll take the cultivar choices you have provided and compare them to local wisdom. Thanks again for sharing your collective experience. Two things never cease to amaze me: I) the number of choices there are once you start looking and II) the huge amount of hands-on, hard-won experience that people happily share. Best, Mark

Apricots are not normally grown on their own root or the root of another apricot. I agree with george that you are very likely to be disappointed even if you succeed. In your zone you should consider one of the new low chill varieties grown for your area, if you intend to get fruit. Al