Re-reading my post I realized it was not that clear about moth emergence and larvae hatch - hard to concentrate when also watching my 1.5 yo girl tear around.

Biofix is when the overwintering moths first emerge. I use the day that five moths are counted in the trap.

After this, it takes about 250 degree days for the new eggs to start to hatch. They don't hatch all at once, but start slow, build to a peak, and taper off. By the time the first generation hatch is over, the second is about to begin, so really you only need to know when it starts and keep up your spray coverage. Use the on-line tool, or just start spraying 2-3 weeks after biofix. Depending on the weather, you will have to spray every 10 days or so until fall. You will need a gallon of spray or less (maybe 1/2 gallon with a fine mist) for a few trees - get the undersides of the leaves. The virus specifically targets coddling moths so there is no danger of you getting sick from it.

It's really pretty fun to get these critters figured out!

I have about 25 apple trees, from just-planted to maybe 50 yrs? Most are semi-dwarf, but one Granny Smith might be standard. 10 years ago we bought a place with a variety of neglected trees, and thus the hobby started. Only 3 mature trees tend to bear every other year (Winesaps I think, though not sure as I didn't plant them), but through pruning and hand thinning I have brought them back to bear every year. I don't hand thin them all, and don't think I could find the time to squeeze all that thinning between bloom and hatch, so I concentrate on a few. Some trees just produce fruit every year no matter what - the Granny in particular is super productive, but I'll lose every fruit to moths if I don't do anything. This year I am toying around with the idea of spray thinning, leaning towards salt solution, but don't look forward to turning everything brown. Hand thinning is really tedious to me.

It only takes about 45 min to an hour to spray them all, walking, quite an enjoyable task every week or two. I guess I would not like to put 1000s (?) of plastic bags on the trees, if no other reason than they are plastic. It certainly isn't about cost; not that I don't care at all about cost, but half (ok, more than that) the fun for me is in the experimentation/learning. I have tried other things to control moths too, none too cheap, including confusion lures (making an artificially large block that extended well past my somewhat dispersed orchard) and Trichogramma wasps. Teaching myself to graft has been fun too, and I am in the process of re-working some red delicious trees not planted by me.

Also, I am foolish enough to think that someday I'll plant at least a few hundred trees and sell locally - there would be a good demand here I think for local organic heirloom apples - so all this work might be put to good (?) use. Actually last year I did sell some apples to the local co-op; I certainly can't use all the fruit these trees can produce myself! I have the land, and my wife has already said she would give up the front horse pasture. a south-facing hillside.

Hi- to minimize the effect of any spraying that must be done- do it when bees are not flying. Often we dont know if these sprays are 'completely' safe for our beneficials.

I've got 3 apple and 4 pear trees here in NE Portland that I have been growing for about 12 years. I have had success without spraying insecticides on my trees. I use Japanese apple bags. They're the ones with with paper on the outside and a kind of waxy paper on the inside. People question the labor intensity of this practice but I quite enjoy spending several June evenings in the trees bagging fruit. It goes pretty fast once you get the hang of it. I also thin the fruit while I'm in there. The nicest part is that once the bag is on, you don't need to do anything more until harvest.

I get several seasons out of each bag. Wasps come and harvest the pulpy outer paper on the bags some years, making striped furrows in the bag and decreasing its' longevity. I have tried paper bags and plastic bags in past years. I think the Japanese apple bags are easier to put on and keep the critters out better.

Last summer was particularly bad for coddling moths. In many cases they bore right through the bags. The majority of my crop was without damage though. The moths seem to cycle and get real bad every 3-4 years. I'm hoping last year was a peak.

I still have to spray sulfur a few times in our warm and wet months of May and June.

I have used neem oil on perennial vegetables, particularly artichokes with very good results. I have not used it on fruit trees.