Probably just old leaves the tree is getting ready to discard.

I don't see a deficiency, Ken B is correct, just old leaves.

I was hoping that was the case. I thought it strange that the discoloration was isolated to one cluster of leaves, which also happens to be one of the oldest clusters on the tree (over 1 year old). But, they haven't dropped in a couple of weeks of looking like this, and I'm always worried about overwatering, so I thought I'd check in with others :).

Hi, Travis. You didn't mention whether or not there is fruit distal to the affected leaves on the branch with chlorotic foliage. It IS very common to see conspicuous chlorosis on foliage of fruit trees proximal to developing fruits. You might be interested in what I recently posted to another thread on this forum:

Trees and herbaceous plants prioritize actions that require food/energy, but perhaps it's better to say that the strength of energy sinks has a distinct order: Energy is first allocated to respiratory function, i.e. to maintenance of living tissues, then, to production of fine roots, followed by flower and seed/fruit production, then primary growth (extension of both roots and shoots), then secondary growth (thickening), and finally, the synthesis of defensive chemicals. Allowing trees in containers to retain all fruit they set can be very stressful. You're seeing manifestation of nutritional deficiencies because reproductive parts come before primary and secondary growth; and, as you can see from the pecking order, a bumper crop of fruit can affect the plant's ability to defend itself against insect herbivory and/or disease pathogens.

It's very common for bearing branches to show chlorosis as fruit is developing. It might not be that there is truly a deficiency as it is fairly common during periods of rapid growth to show up even when appropriate levels of nutrients are in the soil solution and available for uptake. Blossom end rot is often blamed on a Ca deficiency, but in fact it results even when the Ca supply is appropriate, from a combination of fertilizing at nitrogen levels too high and rapid early season growth. The plant simply cannot take on enough Ca to ensure cell growth is normal during periods of rampant early season growth. I guess the main point to take away here is deficiencies made manifest in foliage are not always due to an actual paucity of nutrients in the soil or soil solution. Some deficiencies will be of the physiological variety, others can be antagonistic deficiencies where an over-abundance (redundant?) of nutrient A can make it very difficult for the plant to absorb an adequate supply of nutrient B. Say you used a high phosphorous bloom-booster fertilizer because you felt it would produce more blooms and thus, more fruit. Your plant might easily show interveinal chlorosis because phosphorous is a known antagonist of Fe (iron) and several other nutrients (calcium, potassium, copper, zinc).

Given the condition of the rest of the plant, It's likely a case of natural senescence with the affected leaves still in the initial stage of abscission, that being resorption, during which the plant proper reclaims mobile nutrients and other biocompounds from leaves which the plant recognizes (via its chemical messengers) are not pulling their weight. There are also other factors with the potential to cause localized chlorosis in that group of leaves. Root congestion causes loss of the trees oldest foliage and foliage most proximal to branch apices. Over or under-watering is a possibility, as is low fertility, especially deficiencies of N, P, K, Mg. A damaged or diseased root that primarily services that branch is also a possibility as it would affect oldest leaves first. In fact, most cultural adversities other than drought stress and deficiencies of the immobile nutrients are first made conspicuously manifest in older foliage. I added the word 'conspicuous' because results of stress factors can always first be measured in roots.

Generally speaking, the first fruits trees produce are not as tasty as fruits from the same tree after it's had an opportunity to develop further. You might consider removing the fruits, even new blooms as they occur, which will free up a considerable amount of food/energy the tree will then use to increase its mass and develop.

Al

600 words, just to say it is probably senescence (old) leaves??

Al's informative postings are so long that I often have to search for his answer.

One possible solution to this problem is for Al to include an abstract/summary at the beginning of his posts so that readers will readily find his answer without searching while those interested in a more detailed explanation can still have all the details.

Thanks, Cassie - for the kind words.

@Vladimir (Zone 5b Massachusetts) - I appreciate the fact that you tried to contribute something constructive to Travis's thread instead of being a part of using the length of my post as an opportunity to vent vindictiveness. I have some thoughts:

For those who think my posts are "too long", consider this. You're probably not who I'm writing for or addressing. I have often acknowledged my posts are longer than those someone else might offer. The reasons are several.

First, the more reliable information someone finds in front of them, the faster they learn. When I started growing things for fun and food, there was no internet. That fact provides me with an understanding of how much faster we can learn when the information is always at our fingertips, saving us from need to pour over text after text to gain even a rudimentary understanding of how things work. When we already know something (a stove might be hot) seeing the information again is always superfluous and unnecessary except as it serves to reinforce what we know. Fortunately, I'm not trying to reach those who already know, or think they know, all they need/ want to on any particular topic. I look to reach those with an actual desire to learn and willingness to act on what they learn to enhance their growing experience. I write for them and anyone else who comes across the information, be it on the day it is written or many years later. I know the validity in that manner of thinking because A) I get at least 10 notifications daily, where someone took the time to like something I wrote many years prior to their 'liking' it, B) because of the number of times people have thanked me for going into depth/ detail, and C) because have never had anyone take the time to write a note to thank me for being brief and not paying attention to details and/ or not taking time to qualify an offering, however, I have received hundreds of notes of thanks for doing the opposite. Our attention to detail and how well we are able to qualify the things we say are what cement our credibility in the minds of others; and, if we want people to trust the things we say, credibility is the medium of exchange.

My goal here is to help others learn what it takes to get more from their growing experience - to make it easier, through sharing, for others to learn what I have learned while minimizing the amount of effort it takes. If I don't care how many words it takes, why should anyone else? I'm willing and glad to do the work, counting it as a natural extension of my own growing experience. Whenever there are those who feel what I write isn't worth the effort to read, the simple solution is to skip over my offerings, ignore them. It won't bother me a bit.

I would make one observation though, about sifting through what someone says to get to the information we need. Based on my habitual research to ensure that the information I'm providing is accurate and defensible, I have learned more incidentally than I ever could have imagined. I've stumbled on topics and discussions I didn't know existed, and countless times uncovered bits of information that proved to be keys to better understanding topics that enthrall me. I don't imagine it would be any different for anyone else.

Al

Having someone with experience take the time to be comprehensive is a precious commodity on these pages.

tj

Al, thank you for responding. I do often find your posts informative, so please do continue posting your long but informative posts.