How do you know when the apples are ready

I am watching all my neighborhood apple trees and they are all dropping fruit. None of it is ripe, but they are dropping anyway. Its obviously too early now, but how do you know when an apple tree is producing good apples?
Scott

Taste 'em I guess. If they taste ripe and they're juicy, they're ready imo!

they will self prune apples, its a way for the tree to put as much energy as it can into viable seeds. oak and hickory trees are doing the same thing now. acorns are falling all over my woods, but none of them are ripe, they're just kicking off the scrawny ones to make sure the good ones get big and delicious.

I've heard that when approximately 1/3 of the trees apples have fallen, then they are ready. Don't know for sure though, I usually just taste and see.

If a lot are falling unripe it means the trees are a bit stressed. One reliable test is to juice an apple and use a hydrometer or refractometer to test the sg, if you can get 1.050 or 1.055 they are getting pretty ripe, though it depends on the season how high the sg will get. In a cool year you may not get over 1.045. Of course the easiest is to take a bite, you want them as sweet and full of flavour as possible. Don't pick them too soon, your cider won't have as much flavour, The main factor in the quality of cider is the ripeness of the apples