Detectives say 20-year-old Rosalba Moran of Oxnard gave birth in the Camarillo-area field in the 3200 block of Central Avenue and left the newborn to die. A farm worker found the baby's body.
Months of detective work, including the use of familial DNA, went into the arrest. More than 100 DNA swabs were collected from field workers in the area the day the baby was found.
One of those swabs led detectives to Moran, a relative of one of the field workers. She was already in jail on unrelated charges. Forensic scientists processed Moran's DNA and confirmed she was the mother of the baby.
Moran was arrested on Dec. 21 and is being held on $1 million bail.
It's unclear why she left her baby to die. Detectives say it didn't have to be this way. The safe surrender law allows someone to give up a baby legally.
"In Ventura County, you can drop off a baby at any county fire station or any county hospital if you don't want to have the child," said Capt. Don Aguilar of the Ventura County Sheriff's Department.
Authorities are trying to identify the father of the baby. Anyone with information is urged to call the Ventura County Sheriff's Department at (805) 383-8786.