Help with crown and trunk rot on Apple

Hello again. :blush: This is a three year old Apple tree that I bought as a four grafted variety from IFA. Since planting it I have had to cut it back a few times to add two other new varieties onto it. So now it is a six in one apple tree. I have spent a lot of time on it and would really like to save it if possible. It seems as if it has crown rot or trunk rot and I was reading on Penn State university and their recommendation was to carve back all of the bark that is infected to allow it to air and dry out. is this correct or did I read it wrong? Is there any other recommendations that you professionals recommend?

In the beginning of planting all of my trees I have been watering them with a water well around the tree that included the trunk. I wish I would’ve known that it could potentially cause this problem. Since then on this tree I have excluded the trunk of the tree in the water well. I am switching to a drip irrigation system in the next few weeks that will go in the drip line of the tree and not close to the trunk. What are your thoughts on treatment of this tree?

Trunk spray with Phosphorous Acid (Agri-fos) or Aluminum Tris Phosphonate (Aliette) and an Adjuvant (Silt/Pentra Bark).

Search for keystonepestsolutions, I found them at less than half the price of other sites. (No relation, just had to deal with 30 year old mature trees dying in droves from SOD.

Ok. I will look into those. Would cutting back the bark help?

It would make sense if there was an active canker site. The photo makes it look like it’s spread from root up, so doubt it would do anything good in your case. I’d be worried about damaging good cambium accidentally.

I would do both a trunk spray and a drench, maybe a bit more of a distance from the crown and the mound. Sooner the better, while your foliage is still looking green.

Ok. If I do a drench how long until I could grow apples on it again for consumption if it even survives? I would imagine cutting all the growing apples it has currently on it off would be good to put the energy into the tree?

These are the two that I found. Is there a difference between the agra phos and the garden phos? They contain the same amount of phosphorus acid and instructions are the exact.

Also I have some liquid copper from the spring when I sprayed the trees would this help at all? Or is the phosphorus acid a better choice? It is the Montery’s liquid copper 27%

Agri-fos is from the manufacturer. (Reliant). I think Garden Phos is just a relabel. They are both the same. For oomycetes (phytopthera), phosphorous acid is one of the very few remedies. Copper doesn’t do much for root rot.

The label / booklet for agri-fos contains tons of detail on application. You definitely should read it. It includes information on how many days before harvest etc.

Here’s a link that is a bit of a summary for a quick idea on how long before harvest (PHI, pre harvest interval) .

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Definitely looks weird! Are you sure that the rootstock isn’t just a different color? If it is indeed rot, it would probably be cheaper to just buy a tree at a nursery and top work it next spring. Hopefully a few more orchard chime in.

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I just zoomed in, that is definitely not healthy looking.

If you are not attached to this plant, it would probably be cheaper to replace. However you do have to clean up this one fully, roots and all. Getting rid of phytopthera in the ground is hard to say the least.

I do believe it is right. It started at the very base of the tree only an inch above the ground and then since spring has slowly crept up to now almost 1 foot.

I’m not quite 100% attached. I have had multiple problems with this tree. So I could replace it. I just hate to have wasted several years of patience and time. It take so long for fruit trees to bear fruit. :pensive: so I guess if I had to pick I will try to save what I can on this one.

Let’s say I did rip this one out would I still have to treat the ground anyways because of the fungus that is living there? If I planted a tree in the same spot without treating the ground I would end up with the same problem correct? If that’s the case either way I would have to treat the ground.

I guess life has many lessons. I wish I could go back and create a larger watering well and a small one like in the photo. To keep the water away from the trunk. I only did that a few weeks ago and I wish I would’ve done it from the beginning.

Your saying use this instead? Or is it sixes? I’m happy to purchase whichever one you think would do the best. In the instructions it says to drill into the bark is this necessary? Could I inject it with a needle and syringe? Or is spraying it on the trunk just as good?

This is exactly what I used. The tree injections need some specialized tools like arborjet. If you use an organosilicant like petra-bark or silt, you can avoid the hassle. For small caliper trees with thin cambiums I don’t see how you can really use any injection systems. I just used the trunk spray for my fruit trees (pomegranates, cherries, almonds). I even cut a cross section on a branch to see if it actually got in through the bark, it certainly did.

If I were you, i’d try to ‘fix’ the tree in place, worst case it dies, but at least you tried to kill the disease in the roots. Hopefully reduced the chance of reinfecting a new tree.

To be clearer, I’m saying get this and pentra-bark, spray the mix per ratios recommended on the label, and spray on the trunk and crown.

Cool. Thank you very much for your help. I will give it a try and hopefully it helps. I really do appreciate your wisdom :+1:.

Hi. I’m sorry to keep bothering you with this. But I do appreciate your help. I got my Reliant and pentra bark in the mail and I am ready to apply it. I was reading the instructions and there is only a section that talks about basil bark spray and foliar spray. It doesn’t talk about drenching the roots of the tree. It does state to spray down to the ground level until runoff occurs and saturation. Do you suggest me mixing to The mixture of the basil bark spray and then drench the roots after spraying the trunk?

So for example there are some applications of pesticides and what not for trees where you mix a specific amount in a few gallons of water and then drench the root area roughly 2 or 3 feet out from the trunk. Is this what you mean by drench or did you just spray until runoff?

I would imagine the best treatment would be to both do a basil bark spray and to mix the amount in three or 4 gallons of water and drench the entire root area. What are your thoughts? And if you did drench the roots on what was your mixture.

From the Agrifos label. Soil drench 6 1⁄4 to 12 3⁄4 fl. oz. per 100 gallons. I went with the higher number.

Have you cut into that discolored bark ?
Is it green ?, and alive ?
Brown ? And dead ?
If brown - dead, no sense in the treatment.
If so ,only a inarch graft would save it.

It’s brown but it is spreading up the trunk. It is about 7 inches higher than a a month ago. The tree is still doing OK so I’m going to just try Fruit and a suggestion. If not I will definitely look into that option.

That’s weird. It doesn’t state anything on mine. But I will go with what you say. Thank you.