Answer: Lady bugs are considered beneficial insects and would not be harming your tree. There are a number of pests that may attack birches but based on the information in your question I am unable to determine what is attacking your tree. You might wish to take a sample to your county extension (840-7408) for a specific identification of the pest and their most up to date recommendations of how to treat it most effectively. They may also have some general recommendations on birch care in your warm summer area.
Q&A Library Searching Tips