Asian Pear Insect Damages

This is the first year that my Asian Pears set lots of flower and fruitlet.

Yesterday, I inspected and found quite a few of these fruitlets with a brown drilled hole on them. What is it and is it serious? Should I prune off the marred fruitlets? And if you let it grow, would it grow? And would the infected pear tastes like good one at harvest? Or it’s just a cosmetic mar?

And I guess the more important question is, if this is a serious disease, how do I prevent this from happening next year?


A brown drilled hole with frass coming out is probably codling moth. I would prune those out unless all pears are infected. Spraying is needed if the problem is bad. I use Surround as well as codling moth granulosis, a special virus that kills only codling moths.

Wow. That’s fast! Thanks Scott.

I’ve been trimming off quite a few and any under-developed fruitlets. How and when do you use the Surround, now that fruits are hanging everywhere along leaves?


Ah its good you added the pictures, that is plum curculio not codling moth. I don’t get much codling moth in pears but curculio can be a big problem. I use Surround on it in April-May on the fruits and branches. There are also a lot of chemicals you can use, I prefer Surround since its not toxic.

At this point the damage is already done, just make your plan for next year. If the pear is not growing deformed it will be all good except the little spot on the skin and you can keep it. If it gets deformed it will still grow to maturity but you will need to eat around the bad area. Often you can thin out the curculio damage by removing all the worst ones in a cluster.


You still have time to bag some of the fruits that have not been bitten.


I’ve been removing quite a few until I felt alarmed. Does this “plum curculio” disease come at once? Or it continuously attacks the rest along the season? I guess the answer would prompt for extra steps like Tony’s suggestion, to bag the fruits.

But I think I still have over couple hundred of fruitlets spreads among 3 trees. My wife and kids may think I’m crazy with pouches growing in the tree! :worried:

So next year action is to spray them with Surround? At what stage?


Spray starting when you see fruitlets up until dime size or so. They tend to hit at the size of a large pea. Curculio come later in the summer as well but the damage is minimal compared to the spring wave and I pretty much ignore them as of about now (in my climate, Maryland).


Scott, this is my first year with actual fruiting pears…that is my own fruiting pears. I first planted them late, the year before last.
I have a few fruitlets with identical drilled holes to Tomil.
Why is it that PC damage in pear looks so vastly different than PC damage in apples or plums? In apples and somewhat less-so in plums (at least early on) I can easily see the trademark crescent or fan shaped borings, but in pears they look identical to Tomil’s,

I had pegged PC for the damage in question, but was wondering why it’s different in appearance?

I spray heavily, but I wait until every single blossom is down on ALL my fruits since for convenience, economical and environmental reasons I only want to spray when maximum effect is achieved. I missed the ultimate timing this year using this method and have seen recommendations of first spray at first pink/white stage. What do you think? My plums again took a hit, but since first app of Imidan has ceased (seems I was close, but missed by a bit the ultimate timing). Early signs of PC had already occurred before first spray.
On the pears, since they are so young, culling is no big deal, but the plum is plenty large enough to support way more fruit than it ever has, so I’d like to get all that it sets.
In your opinion, do you think a heavy Imidan app at first pink/white would be particularly detrimental to bees? Problem is, first pink or first white on one thing may mean near full bloom on something else.

I think this may be where monoculture has an advantage.

The crescent is cut to prevent the growing fruit from crushing the egg, but I expect pears are too hard to cut the crescent in. I have seen crescents and non-crescents. The main way you can tell curc vs moth is the moth openings stay open for grass exit. This is blatantly obvious on apples and pears, but can be hard to tell apart on stone fruits (unless it rains – goo will come out of OFM holes on peaches).

I don’t know about Imidan timing since I don’t use it. You could always put down Surround early, its non-toxic to bees, and switch to Imidan when all the petals have fallen.

I was just out putting down another Surround coat. I did really well all spring until the end here, I thought the curc was done but she was still active and I got a lot of late bites. The late bites are not as bad as they don’t distort the fruit so much and you can just cut it out and eat. Still, gotta remember to keep it up a bit longer next year! Imidan is much easier on that point, dead curcs aren’t laying more eggs.

Awesome…makes sense. Thanks Scott. The early Surround is a great idea too!


That’s an interesting observation. I’ve mindlessly seen both kind of damages: round and crescent openings on the same tree from both type of fruitlets, A. pears and pluot, but had no clue of the difference.