My dog's scrotum is red, black, and has open wounds. What to do?

Hi there and thank you for using Petco Pet Education Center, formerly Petcoach to address your concern. If Tomy sat in something irritating, it may have lead to him licking and chewing at his scrotum. I would recommend getting a plastic cone and placing this around his head and using an ointment such as Sentry Wound Cream which can be found online or at your local PetCo. If the wound does not improve or it worsens, I would recommend having a veterinarian examine Tomy so that the most appropriate diagnostic and treatment recommendations can be made. I hope this helps! Please let me know if you have any other questions or concerns and I would be more than happy to help you further.