Tackling pests on a pear tree

Q: I have had a pear tree for about four years which had masses of pears last year. Many had a little bug going down through them. I was also getting fungus on the branches which I painted with methylated spirits, but now the tree looks as if it is dying. The little pears have dropped off and the leaves are sparse and droopy.

A: The pest in the fruits was codling moth. It is too late to do anything about that now, but you can help to prevent it next year by investing in pheromone traps to catch the males. As trees get large and crops become heavier, the codling moth – though still present – is usually less troublesome because there are always plenty of undamaged fruits.
What you describe as fungus may be canker. This is bacterial rather than fungal and results in thickening and cracking of the bark which becomes swollen and distorted in places. It cannot be cured, but, where possible, prune out branches which are badly affected. When a tree is stressed with canker the problem is often made worse.
The loss of this year’s crop and the drooping leaves, suggest that your tree is badly stressed. You should remove any remaining fruit as soon as possible and make sure the tree is in fertile soil with no grass or competing plants at its base.
Don’t be tempted to feed at this stage, but make sure drainage is good. Don’t let the soil dry out too much, though.