Just wanted to pass along to my friends here my experience with G.30 apple rootstock. Two of my 4-year-old G.30 trees broke last summer at the graft. Both were about wrist diameter. Resulted from carelessness on my part: I had staked them to T-posts with twine, and I had not noticed the twine had broken. The trees snapped on a windy day. I budded them myself, and the union looked good. I had been cautioned about G.30 brittleness--it is not recommended for use with some varieties. And using standard grafts is a challenge because of the brittleness. Only budding works for me.

If I were starting my orchard again, I might consider using B.9 exclusively. I have a couple of trees on this rootstock, and they are great (staked of course)--compact and high yielding.

I had high hopes for G.30 as a new replacement for M.7, but I don't think I would recommend it now. Yes, it is precocious, but unless it is staked securely, you might want to consider another rootstock. I consulted Steve Cummins, from whom I buy my trees and rootstocks. I don't think he would mind if I include his comments. I have had very good experiences with his nursery.

"The jury is still out on G.30. We have more reports of people loving it and dealing with its limitations than we have reports of snapping at union. We had hoped that G.222 was going to replace G.30 at the 50% vigor mark, but it looks now as though it is coming in at M.26 35% instead. G.890 and G.210 we are just now starting to work with, but have no experience thus far. So at this time, M.7 and G.30 are the only choices in the true 50% class. They both have their pluses and minuses. If permanently staked, G.30 has been a great stock for most people.

In the 35% class (B.9 is considered 25%) There is G.222, G.202 and G.935. I have not heard of any issues with any of these stock.

http://www.cctec.cornell.edu/plants/GENEVA-Apple-Rootstocks-Comparison-Chart-120911.pdf "