Sure is a leaf size difference. Give us a pic from the ground up about a foot or so. I see what may be off colored leaves too. Ph might be a concern.

Almost looks as if your root stock is over growing the grafted variety. Are any of those lower shoots sprouting from below the graft line? That could cause it to be unproductive. If you're not sure where the graft is, take a pic of the trunk from ground level up to the first few branches.

id also dig out all that grass from underneath that tree that is inside that water ring line, grass uptakes water and nutrients quicker that that citrus tree can, part of the problem might be that it is in fact not fertilized enough due to too many weeds and grass at the root lines competing for those nutrients, but what the others say is correct take a picture of the trunk so we can see if those are rootstock shoots outcompeting the scion.

Thanks for the feedback! Here are some angles of the trunk, you're going to have to help me spot the graft line.

Those two matching shoots coming from the very bottom are the tall, vertical growth with small, darker leaves. Those seem to be the only branches with those characteristics. The rest, originating higher on the trunk, are the large leaves that are paling from the tips of the branches (those are the newest growth and the only ones that blossomed last month). Here's another shot of leaf size/color comparison.

I'm actually more afraid of over fertilizing, especially in one big dose, because I've shocked nursery transplants before simply by applying the recommended amount. Although it's been in the ground for years, I don't get the feeling this thing has a much larger or stronger root system than what came in the pot.

Cut both of those straight branches, now. And the thin branches above them. Six branches in total. They are rootstock. The graft is on the thick center trunk, where it stops going straight up and goes right then up.

then take more pics and post again so we can be sure there are no more rootstock suckers.

One note about removing the grass, and other growth around the base of the tree . Citrus trees have a very shollow root system. . There are important feeder roots just an inch, more or even less, below the ground surface, or at the ground surface, that belong to the citrus tree. Be very careful not to damage these roots. You just might have to kill off the grass by covering it with something that completely blocks out the sun for a period of time. When you begin to dig under the tree be VERY careful not to damage any of the tree's roots. Remove all vegetation from around the trunk out to the drip line.- Silica

these are the limbs that need to be removed

And cut them as close to the ground as possible, maybe even dig an inch below the soil and cut them below grade. The center thicker trunk with the paint colors is your main tree.

Evan

The ones with the lines through them are also below the graft line

The graft line is below the yellow paint. The other limbs are above the graft, see photo with graft line circled. If it were my tree, I'd cut the two branches coming from the ground and take more photos from the side where the branches are that you cut and let us have another look. It won't hurt to cut the other branches with the lines through them, I just don't think it's necessary.

Evan

Ok, that makes a lot of sense, thank you! I removed those 2 limbs and now that I know what I'm looking for, I'm pretty confident those were the only ones of the rootstock type. The rest of the foliage looks uniform.

Now, should I do something extra in the way of fertilizing? Should I do some light pruning to remove the yellowing tips or just leave it?

The yellowing leaves are a mineral deficiency. The leaves with the dried burnt tips looks like salt build up or possible fertilizer burn. My lemon leaves get tip burn all the time, could have to do with my soil being slightly alkali. You need to carefully clear away that grass below your tree, first, spray it with round up to assist in killing its roots. Use a piece of cardboard to protect your tree trunk when you spray the weed kill so as not to get any on your tree. Wait a week, once you see the grass is yellow get in there and pull the grass by hand. Try to keep as many of the feeder roots from your tree in tact. Once the grass is cleared, go to your local HD and purchase a product called Arizonas Best citrus food, it is best formulated for tres in our hot climate with our soil type. I also used to use the Vigoro citrus and avacado fertilizer but have had much better results using Arizonas best.

My Eureka lemon tree from when I planted it a year and half ago to yesterday.

My citrus · More Info

Evan

I know there will be those that disagree with this, but what has worked for me with similar citrus is to foliar feed by mixing 1 table spoon of Fox Farms Grow Big Hydroponic fertilizer 3-2-6 (not to be confused with Grow Big 6-4-4) along with 1/2 teaspoon of Coco-Wet wetting agent in 1 gallon of water then mist the leaves top and bottom with a pump up garden sprayer. Typically results are visible in 1-2 days. Repeat weekly as needed.

I have tried other foliar feeders, but this is the one that works for me best on citrus. I have also used Neptunes Harvest Fish and Seaweed blend with some limited success at 2 table spoons per gallon with 1/2 teaspoon Coco-Wet. The only bad thing I have found about the Grow Big Hydroponic fertilizer is that it will occasionally clog the sprayer.

Of course your mileage may vary, you are in a much dryer climate, etc.

The other four are clearly below the graft.

it is on trifoliate rootstock in the second picture you can clearly see the trifoliate leaves so i would cut off any branch that is producing trifoliate leaves cant tell in the other pictures if you got them all or not but it looks much better than the first picture.

Maybe what he circled and labeled as the graft line is the graft line.

but it sure looks like it was bud grafted where it stops going up on the trunk and starts to go sideways.

I dont see thorns on the lemon branches. I do see them on the trifoliate and the branches below what I belive is the graft line.

can you post new pics of the trunk and first couple sets of branches?

some times a double graft has to be done to connect some scions to some rootstocks but why would anyone do that?

Okay.... let's go back to the beginning and say what kind of lemon, what kind of rootstock, etc. Some days I get very tired of people asking for advice about "lemons", or worse "citrus". We work for free here; but a little help gets you a LOT better answer

Arizona is infamous for high pH soils; if your pH is above 7.5 your citrus will have difficulty absorbing needed minerals, especially Iron. Application of chelated iron will help a lot; you might want to also add some soil sulfur to lower the pH.

pip, It's hard to show what you need to see in a picture but here's the trunk anyway. (I still need to cut those two stems closer.) I still don't really visually recognize a graft line, but like joshinya said, I've looked at every leaf and all the trifolate ones are gone, and the remaining foliage is uniform. Both types have thorns.

johnmerr, I think it's a Meyer, as for the rootstock I have no idea, I wasn't there when it was purchased and don't remember seeing a label. Sorry for irritating you, I didn't think the varieties behaved so differently that the same general advice wouldn't apply.

Then you got them all. it was possible that the graft was higher, it does look like a bud graft. But looks can be deciving.

The main goal was to be 100% sure. And I think we are.

i don't know if I would leave all 3 branches so close though. The bottom one has the best angle on it.

As silica said citrus have shallow roots but you DO need to remove that grass from inside the water ring by the citrus, grass is very prolific and can uptake nutrients more quickly than citrus roots can i believe now that you have gotten rid of the rootstock feeder branches that were robbing nutrients if you get rid of the grass that is also robbing the nutrients you will see some great color improvement and rapid growth improvement on that lemon tree. i would get down there and pull the grass out by hand shouldnt take more than a half hour do that and get all that grass out then stay on top of it once a week.

Or do by hand in stages, like half now and half in a month. Then every week keep up with it until it doesnt come back.

me personally I would use the black cloth to cover the grass and let it die from sun starvation. Cloth not plastic.

cloth is a great idea, i was thinking to suggest that but i didnt even think of cloth i was thinking plastic but that could damage the citrus roots, i always assumed it was plastic that people layed down lol i dont know why i didnt realize it was cloth to keep temps and breathability good.