Plums Have Maggots
Why have my Victory plums got maggots in them, and how can I prevent this next year?
Certified GKH Gardening Expert
They are likely apple maggots, which can actually affect most tree growing fruit. This article describes how to control it on apple trees, but the methods are the same for all fruit trees: http://www.extension.umn.edu/distribution/horticulture/DG1007.html