Direct answer: Beech tar is a hardwood tar produced from beech wood. It is best known as a source material for beechwood creosote and other smoky distillation fractions.
Beech wood can be heated and distilled in the same broad way as other woods, but its tar has a particular chemical profile. Historical chemical writing often connected beechwood tar with creosote, a phenolic fraction first identified in the nineteenth century from wood-tar distillation.
Beech tar and beechwood creosote have appeared in wood preservation, chemical manufacture, flavour and smoke research, and older medical literature. For a safe public information site, the strongest angle is material history and chemistry rather than practical use on the body or food.
Beech tar is a hardwood tar, so it belongs in a different cluster from pine, spruce, and fir tars. It should also be separated from coal-tar creosote, which became the dominant industrial wood preservative and carries stricter regulatory and hazard issues.
In short: Made from beech wood by heating or distillation. Historically connected with wood-tar creosote. A hardwood tar rather than a conifer tar. Best treated as a specialist historical and chemical topic.