We have been renting for 2 years and our garden has a number of fruit trees that we really heven’t taken much advantage of yet.
Most numerous are about 6 pear trees that this year are producing a fair number of decent sized fruit despite the dry weather.
However, the fruit are full of worms. I realize that it is too late to do anything about it this year, but what are the preventive strategies to get some edible pears next year?
Paint that special glue or slime or whatever it is on the trunk? Apparently putting eggshells in a popsock and hanging them in the tree is a solution. I got horrible wormlooking caterpillars in one pear tree (the one that bothers producing anything) and hoped the birds would sort them out, but no.
Figs are fab this year though.
Don’t know why but my mind first went to bars of soap you could see through, anybody remember Pears?
As regards the fruit, I planted a pear tree in memory of my brother who died young. Took a couple of years to bear fruit and when it did it was swarmed on by wasps, not worms. Not wanting to interfere with nature we picked what we could that was ready and left the wasps to their own pickings in between. But after another couple of years the whole tree just withered away.
I am sorry that that does not help you but my only thought would be to put very fine netting over the whole affected area in the Spring perhaps and tie it tight around the trunk. 
Now is the time to start to protect for next year. Also collect brown paper bags (like from market with fruit and veg) and cut base so like a sleeve. Next year once pears start to form pop bags over and secure at top, which should keep the moths at bay. Obviously time consuming, but you could do enough to protect some fruit.
You can make simple traps for caterpillars from ordinary corrugated cardboard. Use a four-inch-wide strip and wrap it snugly around the tree trunk. The corrugation should be vertical (up and down the trunk). You can use staples to attach the cardboard to the trunk; it should be at least a foot and a half above the ground. Caterpillars will crawl under the cardboard and use the “tunnels” as protected spots to spin their cocoons. Once they have spun their cocoons, remove the cardboard and destroy it. The trick to using this method is timing it properly. You can catch the overwintering generation of caterpillars by putting up bands in August and destroying them between November and January. For other generations, watch the traps and destroy and replace them when you see cocoons.
Spray with Bacillus thuringiensis from May onwards every 2-3 weeks.
“Sprays of Bacillus thuringiensis at the egg-hatch period may give a limited degree of control of codling moth. However, the newly hatched larvae only feed for a short time before boring into the fruit and do not usually ingest an adequate dose.” (Says national institute of agricultural botany)
if one is going to invest in control measures (rather than our home made approach) then wouldn’t a pheromone trap be more effective?
We use the Bacillus for box moth larva, and works well as long as they are out of the cocoon,
Worked fabulously chez moi.
Strangely enough, although our apples are badly affected by codling moth, the pears aren’t. On the other hand, asian hornets (and not european hornets) seem to land on the unripe pears and eat them, starting at the stalk and working down. I’ve not seen this before this year,
Thanks. I’ll try the cardboard. Does it hang together during the wet winters, though? I also have some BT I can use next year.
You take it off. Work out the life cycle in your area but generally put it up early spring, and remove it and all the cocooned caterpillars in autumn.
This worked for our peaches.
Bacillus thuringiensis, will kill most garden caterpillars on fruit or veg if applied when needed. I’m currently trialing on my project garden, so far so good on the brassicas.
I wasn’t previously aware that this is not approved for use by ordinary gardeners in the UK, but only by professionals. Does anyone know the legal status in France ?
The glue or the eggshells ?
I didn’t know this. Available in France in garden centers, brico shops, Super U, Auchan etc
Eggshells.