Poorly cordon apple tree.

[digon]

I planted a 1yo. m26 Honeycrisp apple last February and it did well all summer even producing a handfull of apples which I removed back in June except for one which I left to try.
A few weeks ago all the leaves on the top half of the tree turned half yellow and curled up. A few days later they all turned a deep mahogany and dark green colour but still remained curled up. Since then a few new shoots have sprouted and are normal colour but the other leaves have remained curled and mahogany coloured.
Through the summer the tree has been watered at least once a week and fed every 3 weeks with Tomorite.
Does anyone have any ideas what this is?
Is it a mineral deficiency or a disease?

[FB.]

The dark purplish tints on foliage shortly before leaf-fall can be a sign of crown rot or some other impairment to sapflow such as canker. It can also be a nutrient deficiency.

Can you take pictures of the base of the trunk from ground level to a little above the graft?

Are there any discoloured, cracked or sunken areas of bark anywhere at all on the tree?

[orangepippin]

It would also be useful to see the stem of the tree between where the leaf colour changes from green. Nutrient deficiencies generally affect the whole tree, whereas in this case the top part of the tree looks very different to the rest.

[FB.]

It would also be useful to see the stem of the tree between where the leaf colour changes from green. Nutrient deficiencies generally affect the whole tree, whereas in this case the top part of the tree looks very different to the rest.

Yes, I suggested a whole-tree inspection for unusual bark because I'm wondering whether a canker has girdled the trunk, or whether crown rot has girdled/part-girdled the ground-level trunk or the root(s) which supply that part of the tree.

If it is crown rot the tree is likely to die. If it is canker there might be a chance to save the tree if action is taken quickly, although in my experience by the time a tree looks like that the canker has often spread to other parts of the tree which ultimately proves to be incurable and the tree is lost.

This is one of those times when finding the problem is a matter of great urgency because the tree's survival may depend on a quick diagnosis and treatment.

[digon]

This sounds a lot more serious than I thought it might be. I'll have a good look over the trunk tomorrow before work.
It would be a real shame to lose this tree as it was perfectly formed for cordon use with short branches the full length of the trunk when I received it. It's grown about 600mm in hieght/ length this summer.

[FB.]

Some pictures to try to show what you're looking for....

1: canker (usually a branch disease but can sometimes attack roots, lower trunk and fruit).

2: crown rot (usually a root disease but can sometimes attack trunks, branches and fruit).


.

[digon]

As feared there was canker girdling the trunk coinciding exactly with the change in leaf colour.
I've cut it back to a couple of nodes below the canker which is a healthy looking fairly upward looking bud. I put some wound paint on the cut end.

The rest of the tree/ trunk looks healthy but should I take it out or spray it with something, like Bordeux mixture to prevent it spreading to my other trees? This is the first tree I've had with a major problem.

[FB.]

Check the tree at least once per week over the next few weeks because quite often canker will have already spread an unknown distance further down the stem or even to other parts of the tree but isn't yet visible.
There's a high risk that your battle with canker isn't over yet.

[seneca196]

Sorry to see your cordon as it is, but hopefully it will recover. I was wondering how your cordon was set up? I Can't see any wire work, or lateral support in anyway. Is the bamboo the only thing it is attached to? How have you kept it at the oblique (45) angle? I'm planning a line of 5 similar oblique cordons and was curious to see how you did it.
thanks
(PS. If anyone else reading this has a set of oblique cordons, I'd be interested to see how they set theirs up. Pics. or descriptions would be greatly appreciated.)

[FB.]

I plant my cordons upright - sometimes called minarettes. It saves having the rather unsightly post-and-wire support.
Even on the weak-rooted M9 they won't fall over if they're grown in a sheltered position and don't have the great topweight of a bushy canopy.
One point about upright cordons is to make sure they are well-branched low down early in their life because the more upright they are, the more they prefer to put on new growth at the top and very little lower down.

[digon]

I was wondering how your cordon was set up? I Can't see any wire work, or lateral support in anyway. Is the bamboo the only thing it is attached to? How have you kept it at the oblique (45) angle? I'm planning a line of 5 similar oblique cordons and was curious to see how you did it.
thanks

I have a 2.5 mm galvanised wire running horizontally half way up and another one near the top of the fence. They are nailed to the posts with 15mm staples. The bamboos are tied to the wires and I put a kink in the wire with pliers where the bamboos are tied to stop them sliding along.
7 of my 8 cordon trees have been supported by these wires for four seasons now and they seem to be holding up ok. I don't know how they'll perform with fully mature trees though.

[seneca196]

apologies for bumping this thread, but something has got me thinking.... cordons: vertical VS oblique? The theory goes the oblique variety is better at producing fruit and more productive. Apparently, the 45 degree angle reduces the cordons growth rate and instead directs it toward fruit production. The vertical variety must therefore produce a bigger/taller cordon, favouring tree size over fruit production. So the books say, but as ever I'd like to get peoples verdicts based on any experiences they might have. As the minarette form is very popular and often mentioned on these boards, I'm figuring there are some good things about it, other than not having to install wires.

[FB.]

apologies for bumping this thread, but something has got me thinking.... cordons: vertical VS oblique? The theory goes the oblique variety is better at producing fruit and more productive. Apparently, the 45 degree angle reduces the cordons growth rate and instead directs it toward fruit production. The vertical variety must therefore produce a bigger/taller cordon, favouring tree size over fruit production. So the books say, but as ever I'd like to get peoples verdicts based on any experiences they might have. As the minarette form is very popular and often mentioned on these boards, I'm figuring there are some good things about it, other than not having to install wires.

Minarettes will tend to grow more at the top than the bottom. The higher up the tree and the more vertical the shoot, the stronger that shoot is likely to grow.
A 45-degree angled cordon thinks it is a branch of a larger tree, so tends to behave like a fruiting branch and is less likely to grow mostly at its tip.
It's to do with the way the hormones flow through the tree. Growth-promoting hormones accumulate in the highest parts (and induce strong growth) while growth-suppressing hormones accumulate in the lower parts (and inhibit growth which might compete with the top of the tree). An angled stem therefore has less of a differential in the hormone accumulation.