From the introduction:
Herbs have been a staple of fantasy literature for many years. Striders use of Athelas in “The Lord of the Rings” to cure Frodo, and Polgara’s herb lore in “The Belgariad” and “The Mallorean”, and Raistlin’s use of herbal teas to calm his cough in “Dragonlance” are [three] examples that come to mind.
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This guide was written in order to allow a more detailed method of using the Herbalism Non Weapon Proficiency than that provided in the Player's Handbook (AD&D 2e). It may be used only by characters with the Herbalism proficiency. A revised Herbalism proficiency which can be used in any FRPG [also is provided].
User summary:
The document went through three major editions (3rd/4th/5th); the presumed 1st and 2nd Editions were not publicly circulated; the 3rd Edition was not widely circulated. While some game stats are provided, the sourcebook is easily used for any fantasy game.
The document occasionally is encountered with the title "The AD&D Guide to Herbs".