•Forensic palynology is increasingly being used for geolocation.•Palynology was employed as a geolocation tool in the “Baby Doe” homicide case.•Pollen analysis suggested “Baby Doe” lived near Arnold Arboretum in Boston, MA.•Police focused search and identified the victim and arrested two suspects.•Two suspects were convicted in conjunction with murder. First used over 50 years ago, forensic palynology is an important tool for law enforcement agencies. In most countries that use forensic palynology, microscopic pollen grains and spores are traditionally used in criminal investigations to link suspects to crime scenes or items. While still underutilized in many parts of the world, forensic palynology is increasingly being used to determine the region of origin, or geolocation, for persons and items of interest. Drawing upon the experience of the authors using trace pollen and spores to geolocate forensic samples, the types, methods, and variables of this type of analysis are discussed and demonstrated using the Baby Doe case from Massachusetts, USA as a case study. This is not an exhaustive list and every forensic sample is unique so the methods and experience presented here are intended to be a guide for future forensic and anti-terrorism investigations as forensic palynology becomes more commonplace in law enforcement agencies around the world.