Besides growing fruit for sale, I'm also conducting an apple breeding program. (We got some needed rain last evening, and it's in the low 40's this morning, so I have time to post this, after working outside 11 hours a day for the past 3 weeks.) We grow apple varieties immune to apple scab disease, such as 'Enterprise' and 'GoldRush', so they don't need to be sprayed for apple scab. This means the scab-immune apples need only half the sprays (7 or 8 per year) that scab-susceptible varieties such as 'Jonathan' or 'Fuji' do (they need 15 or 16 sprays per year).
These scab-immune apple varieties came from a breeding program that started back in the 1940's. I'm continuing this work by crossing some of these varieties and numbered selections that haven't been named yet. This year I made crosses between 'GoldRush' and Coop 27, a numbered selection with fruit that tastes similar to 'Jonathan'.
To make controlled crosses, I first remove the anthers, petals and sepals from some flower buds on the tree I'm going to cross. Bees won't visit a flower with no petals, so it won't get pollinated by unknown pollen, and I'll later transfer known pollen I've collected from the variety I want to cross with. Fruit I've pollinated will develop without sepals, so I can tell my crosses from all the other fruit on the tree.