Those tall shoot is not a meyer lemon but is poncirus trifoliata. Since meyer lemon scions poison poncirus stock there must be an interstock or your PT rootstock is a hybrid. It should be removed

Whoa, whoa, whoa... how in the world did you determine from that picture that the upright branch is PT? A better picture might prove you right, Steve, but no matter how much I blow up this photo to pixelization, there is no definitive evidence of PT. First things first... take off all that fruit; it is mature and dragging down the tree. Next, post some close-up photos of the leaves on the upright shoots as well as where they originate on the trunk..With that we can give you a better guess about what to do. Best guess for now is your tree is suffering from leaf loss due to significant change in light conditions.

Here we go... This is a pic if the leaves on the tall branches with all the thorns. The lower limbs have all the lemons but no thorns.

Here us a pic if the trunk where it splits into the two branches. Thanks for all your help!!!!

Good call poncirusguy! After reading your post I took a closer look at the first pic and I could clearly see the 3 leaf clusters.

Ginger raglan, poncirusguy gives sounds advice. The long thorny branches that bare clusters of three leaves have to go! This is the root stock sending out suckers. They will bare uneadible fruit... If any. And steal energy from the meyre lemon part.
If you want to train your tree to be taller let it grow, it'll send some shoots up and let them become your main scaffolding for the tree.

Well, as it turns out, Steve was right; he must be a magician. Take off that branch where it leaves the main trunk; it is rootstock and not Meyer; that is why it has trifoliate leaves, either Poncirus Trifoliata or perhaps Flying Dragon, a Poncirus variety that is a dwarfing rootstock.. BTW Meyers normally have thorns; and even more and bigger on vigorous shoots such as yours, which are normally watersprouts.

John

Ginger has a much better picture of the same tree where the PT leaves are clearly visible on a different thread. I recognized this picture and knew that it was PT.

Ginger Cut at the red line in the picture. That is the PT side

Steve

This post was edited by poncirusguy on Fri, Nov 15, 13 at 22:08