Strange small bumps and marks on plum fruit

[TrialAndError]

See the pictures below which say it all. The marks are on the side facing the light but not the shade side.

It's on the plums of a friend of mine and at first I thought it was scab but I can't find any mention of scab affecting plums in the UK and certainly not like this. The variety is Victoria and it's about five years old. Any ideas what it could be?

[FB.]

This year has been a strange year (most years are quirky in Britain!), with the weather being unusually mild and sunny but also lots of rain.
My guess is that the unusual weather has caused canker or shot-hole disease (bactierial or fungal) and the fruits have been affected. Holes in the leaves back up this theory, although holes in leaves can also be caused by slugworms and lumps on plum skins can be caused by insect damage.

Is the tree otherwise healthy and putting out plenty of new shoots?

[TrialAndError]

The tree is healthy and did put out lots of new shoots this year. In fact it was a bit congested so I have taken a bit of a gamble this late in the season and have given it a good prune so that it has a good circulation of air around it. Its closeness to a wall and being a bit overgrown may have all contributed to the problem.

I did have a problem last year with aphids but with a 10 day regime of horticultural soft soft solution got on top of it with very little aphid problem at all this year. I have inspected the tree regularly and have not detected any insects nor any slugworms.

I also have a cherry (stella) a peach and an apple (laxtons superb) all growing on an adjoining south wall all of which have had no problems whatsoever.

Many thanks for your help on this one. Would it be advisable to give the tree its usual winter wash this year plus the wall and ground underneath the tree with a bit of J Fluid and do you think this should put it in good stead for next year.

It seems to be a very odd year all round with fluctuating temperatures and humidity little wonder really we are seeing problems we don`t normally have.

[Nicos]

I noticed yesterday that this is exactly the same problem I have with a plum tree which is fruiting properly for the first time...same spots, same small holes in the leaves.
Yes- lots of new shoots since last year, and a huge black cherry tree about 40 feet away from it.

[grannymem]

I think our plums are infested with plum fruit moth. Most of the plums are ripening early and when cut open contain small pink maggots and black bits (their poo!)
The less ripe fruit seem to be clear. I looked it up on the RHS web pages & they seem to suggest destroying the infected fruit, using traps next year around May time and making sure the soil is clear of any infected fruit.
Really disappointing but...
I did wonder whether the milder winter we had may have been less effective in getting rid of the pests earlier.

[FB.]

I think our plums are infested with plum fruit moth. Most of the plums are ripening early and when cut open contain small pink maggots and black bits (their poo!)
The less ripe fruit seem to be clear.

Pest-damaged fruit is often first fruit to ripen on the tree and is more likely to be dropped a little earlier. Undamaged fruit stays on the tree longer.

Plums can be especially annoying because of the maggot tunnelling around the core and it being difficult to separate the good bits from the damaged bits due to the size and softness of the fruit.

[yummersetter]

Chickens love our plums, with or without wriggly extra protein. Ours gather under the greengage tree hoping their luck will be in and one will fall in the run. When it does, its like a fowlish rugby match.