How early or late can a dog bark before disturbing the peace in Baltimore county MD.?

There are no specific noise ordinances in Baltimore County regarding dogs barking. However, there are general noise ordinances that prohibit any noise that is "loud and disturbing" between the hours of 10:00 PM and 7:00 AM. If a dog's barking is considered to be "loud and disturbing" during these hours, it could be considered a violation of the noise ordinance.