Flat Apple Disease

Your Red Delicious apples develop flattened fruit with shallow stem cavities, particularly on lower branches. Cherry rasp leaf virus, transmitted by dagger nematodes, causes this. The virus lives in orchard soil and weeds. Prevent by planting on uninfested sites and using virus-tested scion wood. Once established, the virus spreads very slowly.

The use of virus-tested (and found to be free of all known viruses) planting material is important for control. Avoid future orchard sites that test positive for the presence of the nematode.