Flora:

Is there a particular reason why you apply dormant oil to your apricot trees in spring? Dormant oil can be helpful to apples and pears, but apricots often need one or more dormant sprays with copper to ward off fungal diseases. Dormant oil is intended to kill overwintering insect eggs on the tree itself. I do not apply oil sprays to any of my stone fruits, since there is no reason to do so in my view. But I always apply two sprays of copper during the dormant season to peaches, plums, and apricots, one early and one late.

Oriental fruit moth larvae can enter an apricot through the stem, leaving no sign of entry on the skin. These larvae can cause rapid deterioration around the pit. If you have OFM around where you live, organic principles may have to be set aside, since early sprays with an insecticide are the only way to control this insect. The oriental fruit moth hatches out its larvae in the ground around the tree, so any dormant spray is ineffective. Picking up and discarding dropped fruit is particularly important to control OFM, although if there are other unpicked stone fruits nearby it will all be for naught. Check your apricots carefully, and see if your find a small white worm inside near the pit.

Brown rot is quite a different problem, which shows up as necrotic spots on the surface of the fruit, not around the pit.

Don Yellman, Great Falls, VA

Thanks Don,
It is interesting, we spray dormant oil for aphids, peach twig borer, but also if we neglect to spray, it appears that we suffer peach leaf curl and shotgun hole fungus worse, now is this because we seem to have such cool, wet springs anymore?
I believe we do have the OFM, but on inspection I could not find any worms, however, I will make sure all the fruit is picked up and destroyed & not put into the compost.
What is the spray schedule and what do you use for this? Is it possible to use a rotenone based product for this?
Thanks,
Flora

Hi Don,
Just an update, we supposedly do not have the OFM in BC yet, so this is not likely my problem.
I will still pick up the fruit and destroy though.
Thanks,
Flora

Flora, I dont know exactly what kind of mold this is, but since it is from inside the fruit it must have gotten there at blossom time. The wet weather surely helped it form. I would spray copper a couple times around bloom next year (e.g. at popcorn stage and petal fall). You use a lower dose in the growing season compared to a dormant spray.

Scott

Flora:

I see this type mold in some of my apricots, maybe 5%. This is apricots grown inside my greenhouse where there are very few disease or insect problems. I think it is caused by a tiny opening or flaw in the blossom end of the fruit. Notice in the picture that the mold is in the blossom end of the fruit and appears to stretch to the outside on the blossom end. A tiny opening in the blossom end allows a simple mold organism to enter and develope inside the fruit. It is more frequent on some varieties than others. I don't think there is anything you can do about it. But I usually cut my apricots open before eating them or at least look before I swallow.

I have also seen thrips inside ripe apricots with no mold. Thrips are tiny insects hardly big enough to see. But I have fairly often seen them inside apricots indicating that there is a tiny opening to the outside. Of course it wouldn't take much of an opening for mold spores to enter. As far as I can recall, all apricots are freestone, meaning there is an opening around the pit for mold or insects to develope if they can get inside.

The Fruitnut

I think what I have on my plums is brown rot. The fruit gets whitish spores on the outside, and then gets squishy and rotten - there's also a sort of golden syrupy ooze that develops on the outside of the plums.

In the early summer, lots of hard mummified fruits drop to the ground.

This has been happening every year, and every year it gets worse - I am at my wits end because although the tree has lots of character and lends great presence to my garden, the squishy fruits all over my patio (the squirrels really help with this too) are causing me too much work & headache, and I'm contemplating cutting down the tree.

Could someone please tell me, if the copper spray helps, what is the timing and amount of application of the spray?

There also seem to be whitish insect bodies attached to some of the fruit - can I spray both dormant oil and copper spray?