Help protecting plum trees from insect larvae

[AlphaSky]

In my front yard, their are two plum trees which produce quite a bit of fruit. However, for the past two years, in mid spring, there is one day where hundreds of some kind of large flying insect hover over the trees for about 6-8 hours (I suspect they are mating), and then inject their eggs into the newly formed fruits where there larvae grow up, eating and destroying all the plums.

My question is, is there any safe chemicals or other methods I can use to protect these two trees. I really would like to keep the solution pesticide free, so I was thinking of covering the fruit trees with some kind of fine netting, or burlap so that these insects cannot infest them.

Any ideas or suggestions are welcomed.

 

[MotherBrugger]

How tall are the trees Alpha? I'm with netting them, and making a journal with the notation(s) of exact dates these insects show up, so I can begin to get a grasp on when they may be coming. I wonder what they are? Maybe someone here will recognize the life cycle and habit and identify them. I personally am keeping my fruit trees small enough that they can have permanent caging around them, with door to walk in and tend to. Just too many bugs down here to let them even have a whiff of the trees. And I'm not dotting the landscape with these cages either. Mine are container grown, pruned to fit; and all in one, big cage.

 

[AlphaSky]

The trees are about 12 feet high and 6 feet wide. There only about 5 years old, and still growing. Every year it produces more, but its a total shame that it all is lost.

I'm leaning towards netting it myself also, its just that I haven't figured out what the best material would be. I'll need a material that will keep lost sunlight to a minimum.

 

[lesa]

If you able to catch them in the act- I would have ladder and burlap ready. Keep the trees covered until you don't see any insect activity. In a few days when the coast is clear- uncover the trees. A few days without sunshine is not going to hurt them...
Obviously, if they arrive and you don't see them, this idea will not work. The netting would have to have awfully small holes to keep bugs out... Good luck!

 

[MotherBrugger]

It would be good if you were able to catch one of them too, and see if there are organic or inorganic methods (your decision) insecticides to get rid of them. Are they plum curculios? What growing zone do you live in? (helps us perhaps figure what bugs may be in that region) And Lesa makes a good point, if they are really small bugs, so would have to be the netting.
I use porch screening on a screen house (for my plants) that is NOT aluminum, but black plastic. The light gets through, and it keeps out even the smallest of bugs. Only thing I've seen get through it are white flies and ants. If you could find something with holes that small, it might work. Otherwise, dormant oils may help.
In late winters, you can spray dormant oil to control aphids, peach tree borers, (that might be your bug) before the buds on tree start to swell. Do this about a month before spraying any lime or lime sulfurs. Limes will help control brown rot, leaf spot, etc.
Since we don't know your exact bug, you may want to also hang Oriental fruit moth traps in early spring. You can nab the plum curculios we talked about with green sticky ball traps, also hung in spring.
If you know what your bug looks like, maybe you could 'google image' some of the bugs I've named above, and see if they fit the image you have. Then it would be easier for you to find a modus operandum
edit: Don't forget to always remove any rotting fruit that is on tree, or falls from it. If infested, be sure to destroy. Leaving rotting fruit around just invites more pests and complicates your already dire situation.
If not removed and disposed of properly, you could be leaving next years bug-crop 'in the loop'

 

[vfem]

I am terrible and took WAY too much time to create little mesh bags to protect my fruit. I am actually LATE getting them all out and on the trees... but working on it.

Here is the link to the fruit bags: http://www.theeasygarden.com/forum/viewtopic.php?id=30350

Have you tried a dormant spray before the trees bloomed. Organically, we use neem oil... but there are lots of none organic options too.