Newspaper style generally eschews the serial comma. I'm fine with that. Toast, juice, milk and Trix. But sometimes that comma is useful. If I write about a city's departments of housing, parks and recreation and well-being, do I mean there's a department of parks and recreation or a department of recreation and well-being? And what if my series consists of three or four full sentences? For many serial-comma-phobic journalists, the answer to those questions tends to be: Semicolons! Ugly, unwieldy semicolons. Clearly, those journalists did not actually read the stylebook to which they are slavishly devoted. AP specifically says that the serial comma is needed in those cases.
IN A SERIES: Use commas to separate elements in a series, but do not put a comma before the conjunction in a simple series: The flag is red, white and blue. He would nominate Tom, Dick or Harry.
Put a comma before the concluding conjunction in a series, however, if an integral element of the series requires a conjunction: I had orange juice, toast, and ham and eggs for breakfast.
Use a comma also before the concluding conjunction in a complex series of phrases: The main points to consider are whether the athletes are skillful enough to compete, whether they have the stamina to endure the training, and whether they have the proper mental attitude.
So, Walsh writes, it's The departments of housing, parks and recreation, and well-being, notthe departments of housing; parks and recreation; and well-being. Once one of the elements in a series includes a comma, then you want those ugly, unwieldy semicolons: The committees on appropriations; health, education and welfare; and labor.