How to get an apple tree not to produce fruit?

[Leafmite]

Ways to get plants identified: 1) request a White Farm catalogue...very good pictures of a wide variety of plants
2) make a deal with a local nursury to identify the plants in return for divisions
3) look for a local garden club
We have quite a few things that would be difficult to identify. Our chestnut takes after the American Chestnut and people constantly ask us what it is...that should be the easy one. The flowers and herbs will be more difficult.