Disappointing advice given to a friend...

I've just been doing a Facebook "apple welfare" clinic for a friend. She has two young fan-trained trees, and one of them was poorly. When she went back to the garden centre, she was told it was probably apple canker.

When she posted photos, i soon suspected different problems. Both trees are planted within a foot of a new wall. So drought conditions, and un-broken-down mortar residues. The healthy tree had the outdoor electric boxes nearby. The sick tree had a condensing boiler's air-vent on one side, and outdoor water standpipe on the other - so tree was contstantly hot/cold.
The affected branch showed clear woolly aphid "fluff". Very few leaves.

For a garden centre to condemn as "canker" so quickly is so bad. The trees are less than 5 years old, I'm guessing no more than 2-3. So the chances of canker having got in through the bark so quickly? She was given no advice on how to treat the woolly aphid. On a tree that is no more than two leaders (looks like a tuning fork!) it would be less than 5 mins work to treat.

I'm thinking they were just looking at a replacement sale....

Oh yes, and the variety? Jonathan, which scores as susceptible or very susceptible to most diseases, so probably a "thin-skinned" tree.

I hope she manages to save it!

(And yes, I said her top priority - water the poor thing!!)

 

Also treat with a suitable (for edible crops), systemic, insecticide.

 

Err...is there such a thing as a suitable systemic insecticide for edibles? On a huge tree, I can see the logic but on a small, manageable one, I'd go the manual route every time. (Assuming that there will be edible fruit). A bucket of soapy water and a pair of thin rubber gloves if you're squeamish and as Sian says, it's a few minutes work to eradicate pests. At least apples don't have spines! I clean my citrus 'farm' of scale insect by hand because I really, really don't like the thought of using fruit that contains insecticide.
Anyway, back to the apple tree! It sounds like a less-than-ideal situation with all those vents and pipes! Good feeding and watering would definitely help, though....

 

@noisette47, I suggested that she used diluted washing up liquid, and a toothbrush, to clear the affected areas. After googling Jonathan and disease resistance, I said "gentle with the toothbrush"!

 

Thanks to the powers that be in the EU, it is illegal to use anything NOT registered as a pesticide. So even soapy water is a no no.