Apple Tree Disease

[BeloGe]

Hi all,

I have a four year old Bramley apple tree which has been doing fine up to now (possible because I pretty much left it to get on with it apart from the occasional watering and pruning once a year).
The tree carried lots of apples every year so far and this year is no exception. However, a number of apples have developed a large spot on them (see attached picture). The spot is first an orange colour and then turns black from the inside out.

I am pretty inexperienced about apple diseases and don't feel confident enough to make a diagnosis by just looking at pictures online. Any help in identifying the disease and how to treat it would be appreciated.
Thanks

[Two_Sheds]

You need FB ~ he'll be along soon, don't you worry

[FB.]

Difficult to say from just the one picture. Can you do a few more pictures (or answer the questions further down my reply)?
Maybe sun-scorch (due to long, hot, dry weather - my apples have suffereed badly this year).
Maybe a strange presentation of bitter pit (also can be a problem with erratic water supply).
Might be some odd insect damage.

Which variety is it?
Where are you located?
Has it been given a hard winter prune?
Is it growing vigorously as well as trying to fruit?
Has it been given lots of nitrogen fertiliser in the last several months?

It's probably too late to reverse the problem now on the fruits which are already affected, but if the cause can be found, it may be preventable on the remainder of the crop and next year.

[BeloGe]

Hi FB,

Many thanks for your help.

I have attached a few more pictures, maybe this will provide better insight.

The tree is standing (espaliered) against a South-facing wall in Oxfordshire and has a lot of sun throughout the year.

It only got a light prune last year and has not received much fertiliser for some time.

The tree is growing very vigorously indeed, though about 20% of the apples have the spots on them. It starts as a fully orange spot, when becomes black from the inside to the edge.

Many thanks again.

[FB.]

Probably some kind of sun scorch/sun-scald/sunburn - hot, dry, sunny weather.

Not much you can do to prevent it in hot dry seasons.
You could try allowing the fruits to be a little more shaded by leaves.

I purposely grow some varieties in shadier positions nowadays, to avoid sun-scorch.

If the tree is especially vigorous, a hard prune of the soft new growth should bring it back under control - but it must be done within the next week (July is the recommended time).

[BeloGe]

Many thanks for the help. I will try and prune it back somewhat.

One last question - would you remove all the affected apples?

[FB.]

Only prune what you don't want to keep as main structural branches in the future.

I'd leave the affected fruit as long as possible, otherwise the remaining fruit may end up with bitter pit (trees carrying a light crop and growing vigorously are more prone to bitter pit).
I suspect that the non-sunburned side of the affected apples will be usable.

Given the very vigorous new shoots on your tree, I would not be surprised if you see some bitter pit on the fruit appear any time now. My Ashmead's Kernel has just begun to show bitter pit, as has my Fiesta/Red Pippin.