meyer lemon tree

Question

Why does my main tree not produce fruit but an off branch does? Do I get rid of the main tree?

Answer 1

If this is a grafted tree, check to make sure the rootstock hasn't taken over:
https://www.gardeningknowhow.com/ornamental/trees/tgen/can-grafted-trees-revert-to-their-root-stock.htm

If that's not the problem, then I think it's best to leave the main tree trunk even if it's not producing fruit. Otherwise, you might make the tree lopsided and unable to support itself. The leaves on the main trunk are probably helping feed the fruit anyway.