We have come to the point in the season where we get to know each and every tree in our orchard well. Apple trees have clusters of flowers that all turn into apples if the pollinators do their jobs, so on a healthy tree there might be 5-8 apples every few inches along many branches. We shoot for one apple every 8 inches, to lessen the fruit load on the tree - that's a lot of apples to pick off. We especially want to keep apples from touching, since many pests make themselves at home anywhere an apple is touching something. Hand thinning gives us a chance to be choosy about the apples that ripen, so that most of the apples left on the tree are free of bug bites or other blemishes. Larger-scale orchards use chemicals that shock the tree, causing it to drop many apples.
While hand thinning take a lot of time, it gives us a good look at all the trees to see what pest pressures are like this year, any signs of disease, and what the fruit set seems like now that apples are sizing up. It also gives us an excuse to be in the orchard, finding bird's nests, cool insects, and just enjoying this spot we live in.