LE Cook has a pretty detailed FAQ page. The whole thing is worth a read (interesting answer on multi-grafts), but here is a relevant passage.
Simply for safety - of our workers, our customers and their customers. Most Jujube varieties have swords as thorns. You won’t find the kids climbing these trees! In fact when we prune the Jujube, we haul the branches out of the field instead of running a tractor and shredder/mulcher over the branches. The thorns puncture tractor tires - the big tires!
Not to worry - the Jujube trees grow so fast the thorns, I mean branches, will be back in no time. The trees we ship to you grew from a bud in February to a full sized tree with fruit by September/October. They are Fast!
But it is all worth our extra labor. The fruit is delightful and in high demand.
Bold added
http://www.lecooke.com/faq.html
Evidently, drip irrigation and a ton of sun is enough to grow huge jujubes in a single year.