I have not heard or read which fits all fruit tree critters. You did not make dormant spray is big mistake. Japanese beetle are easy to fight with spectracide spray. The trees you mentioned are mostly called stone fruit. The biggest enemy for stone fruit is OFM and codling moth. From my experience fighting the adults is impossible because they are ghosts and they don't damage to the trees. Commercial growers has their ways and resources to fight it. The damage is caused by their eggs which hatch into larva and destroy the new stem growth and mainly the fruit. The best way to fight these critters is to prevent the eggs from hatching.

dohertyc9,

I wouldn't worry about spraying anything this growing season, until you see a problem. At least that's pretty much how I manage my non-bearing trees. An exception might be borers. If you know the area has a problem with borers, that might justify a preventative treatment.

Peach trees bear pretty early, but if yours only had 4 blooms it's likely most (or all) of those will fall off.

Triazicide or carbaryl (Sevin) will help control Japanese beetle. Sevin is probably slightly more effective than Triazicide.

Dormant sprays must be done in the dormant season. Oil can be sprayed in the growing season, but only at a lower rate. At this time, there is probably no point in spraying oil.

The next dormant season, you'll probably want to spray your peach tree for peach leaf curl.

Treehugger,

Codling moth doesn't attack stone fruits.