Cummins said as much in a lecture he gave (Bob Cummins, former Cornell root stock breeder) that I was at years ago. As I remember 333 performed poorly in southern sites. Cally is certainly your most vigorous stock- are trees on them giving good crops reasonably early? I can't use it here because it doesn't take cold.

Thanks Hman. I've gotten a few fruits from most of the other Asian pears after 2 years; this is the first year I've had to thin any of my pears. The cally pears are growing the fastest. The ohf333 pears seemed to grow fine for a year, but it's been slow going since then.

I think that generally for Asian's it's best to go for max vigor- unless you need tiny plants. They are easy to keep pretty small on any rootstock I grown them on. They bear early and continue to bear even if you keep them small.

Following is an archived discussion on pear rootstocks from a noted Houston TX pear affectionado, from the NAFEX list, back in 2002:

"one of the problems in commenting about OH x F pear rootstock is that most of the trials on these crosses seem to have been "hogged" by the groups in the Northwest. This has led to promotion of certain crosses over others that might work well elsewhere. A**** pointed out that OH x F 51 has been ideal for his area(NC), and it is also is excellent for Houston (zone 9) producing a 40-50% sized tree with large fruit. It has the bad rap of not fruiting well, but this is likely a Northwest phenomenon.
The differences in the performance of the OH x F crosses are most apparent in the South, presumably because of the chill differences.
Here, in addition to 51, 40 is reasonable but significantly larger than 51. 87 seems about the same size as 40 but is more precocious, but also does not have the root anchor the first two have. 97 does not work well. 333 is dwarfed nicely, about the same size as 51, but fruits poorly and has smaller fruits.
513 and 217 are bonsai trees.
Pyrodwarf, also an Old Home cross, but with higher chill than most, is even less than a bonsai tree here, growing about 1-2 inches each year.
40 and especially 513, seem to make good dwarfing interstems on calleryana.
Pyrodwarf, however, is not dwarfing in the interstem position.
In colder climates, the differences in these rootstocks must be much less apparent. I recall Ed Fackler(formerly of Rocky Meadow Orchard/Nursery in IN) commenting that after 10 years, it was difficult to tell these apart from each other."

Personally, I have a number of Asian and European pears on OHxF 513 - and have used 8-10" pieces of 513 as an interstem between calleryana and fruiting selections, but it's too soon for me to make a call on how that's gonna work, as I'm only 2-3 years out on the interstem trees.

333 has worked fine for me in Maryland but its clearly no good further south.

Most nurseries seem to agree that max vigor is important for asian pears but I have not noticed much difference between my 333, 513, and seedling asian pears.

Scott

Scott, do you irrigate?

Nope. They are also on a steep hill so the soil dries out quickly.

Scott

I remember Scaper when he was in Austin saying OHF333 hadn't worked for him (this was after I'd planted my trees). He thought OHF97 might work for me. I was hoping Dallas having more chill hours than Austin the OHF333 would be ok, but so far thats not the case.

Many of the well known nurseries here offer Dave Wilson trees on OHF333. Of course they offer Bartlett pears too.

Texas A&M online articles from 1990 or so recommend calleryna, but says OHF is being evaluated

OHF333 seems like a loser here. The OHF97 seems to be doing OK so far, hopefully having higher chill hours than Houston those trees will do ok for me.

But I'm going strickly with Calleryna in the future.