The problem with places like Iseli is that they graft for landscape, not bonsai use. Just about anything that is grafted is going to be perfectly useless for bonsai. Of course, the cutting grown material is fine. This is very frustrating, the problem is particularly bad for conifers because there is usually a distinct bark difference between understock and graft, and give that they are invariably grafted high, you are left with airlayering off the graft as your only solution. On most conifers this is timely and risky.
I was just reminded of this problem this week when I repotted some Gan Seki Sho nishiki black pines grafts I got from Stanley and Sons, another catalog to drool over. This is a cork bark cultivar grafted about 4inches above the nebari with a 2 inch long very ugly side veneer graft. Now that the scion is corking you get a really good idea of how hideous this is going to look for years to come. And these little guys were sold as prebonsai material. I didn't care, I just wanted them as stock plants so I could get some scion wood to do proper grafts. By the way, I think this cv is going to be terrific for small bonsai. Steve Pilacik speaks highly of it, too.
So, yeah, go ahead and drool, but you are better off with professionally prepared bonsai material even if your choices are limited. Great species info though.
Brent
EvergreenGardenworks.com
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