They could be larger if grown from seed but are typically very small or inferior in other ways. Grafting trees was started as a way to get larger better tasting fruit on every tree.

This post was edited by ClarkinKS on Mon, Sep 15, 14 at 19:26

I don't believe they are any larger. I have Tigertooth grown on their own roots. For example apple rootstock was cultivated with different characteristics and many rootstocks are dwarfing or semi-dwarfing. This is not the case with Jujube. Most jujube are grafted to a native rootstock which is very aggressive and propagates readily from the roots. It tends to produce thickets of low quality fruit trees. This is not an issue in an orchard if you simply keep the area around the trees mowed.

One reason I'm using trees grown on their own roots is to avoid the long-term issue with thickets of low quality trees if things are not maintained. Tigertooth do not easily propagate from the root system like native jujube. In fact, when I try to propagate them from root cuttings, my success rate is not great. If you do get propagation from the rootstock it will be the same quality as the parent tree.

I am currently using Tigertooth as my rootstock for all jujube instead of the native rootstock. I'm propagating them from root cuttings and then grafting other varieties to the tigertooth. This allows me to get a wider variety of fruit without the long-term maintenance issue.

The down side is that my trees probably grow a bit slower than trees grafted to the aggressive native rootstock.

But what is the "native" jujube rootstock? Jujube is not even native in US.

Some use Indian jujube, or sour jujube as rootstock. But I do not know what they are. Do we get them from seeds?

By "native" I mean wild uncultivated jujube native in China. In general, orchards get it from root propagation. New seedlings will pop up as far a 30' or more from the tree. They dig them up and use them as rootstock for grafting the cultivated varieties. You are correct that Indian jujube is also used as a rootstock.