Can anyone tell my why part of my Valley Lemon tree has spikes and bears no fruit? It shoots straight up like a pine tree while the fruit bearing part is all wound up near the base of the tree.

Should I keep it there or cut that part off?

Those are called "water sprouts" and will be non-productive. So, yes, keep them pruned out of your tree.

Well it's a 7' tall water sprout then that starts at the base of the tree, which is also where the fruit producing part starts. Should I just cut the whole 5' part off at the start of it?

Thanks for the reply!

Yes, cut off the whole thing. If it is from below the graft, it is part of the root stock - you don't want that either.

Yep ! As Daisy said. Your gonna have to get under tree and cut those branches off, close as you can, and keep monitoring them, as they will want to come back, and sooner is better as those thorns are ugly, nasty booger's, plus they sap lots of energy.
While your under tree, check that graph is well above soil line, as, because those water saps, can come out above the graph, if soil is above the graph. If that's so, cut them off also. 👍👍👍

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