By Seaburngirl
East Yorkshire,
United Kingdom 
A friends pear tree query.
I'm not 'into' fruit trees so help please.
My friend has a comice pear that for the last 5 yrs has been healthy and fruitful. this year the current new foliage has smallish 1-2mm, blisters on the leaves. the old yeaves have turned black and crisp, inbetween the veins.I suspect what ever has caused the blisters ight have 'joined up'.
but can any one tell me what the tree has and more important can it be treated/cured. No fruit but we had horrid weather when it was in flower so I understand why that has happened.
sorry no photo as i didnt take my camera with me.
thanks in advance.
16 Aug, 2012
Answers
I have 5 pear trees on growth limiting rooted stock and well established. Three seem to have a leaf infestation like the one you describe. They were sprayed, as it appeared before fruit set. One fruited well. One did not fruit and seems stressed by the attack. The other not so stressed but the fruit small and sparse. All one can do is wait and see. I think, as autumn approaches, I may prune and defoliate the stressed one to avoid leaf drop to the ground near it, then give a good mulch of compost too and see what happens.
17 Aug, 2012
I've looked at the RHS page and you are spot on Bamboo. Thanks.
She will have to keep an eye on it next spring as her tree is really badly affected and cant pick off the infected leaves.
I will ceratinly get her to remove all the leaves and a good feed wont do any harm either Dorjac.
thanks for you help folks.
17 Aug, 2012
Pear Leaf Blister Mite? RHS has a page on it - no treatments available, but doesn't affect the tree's fruiting ability.
16 Aug, 2012