Player's Handbook[]
Those with herbalist knowledge can identify plants and fungus and prepare nonmagical potions, poultices, powders, balms, salves, ointments, infusions, and plasters for medical and pseudo-medical purposes. They can also prepare natural plant poisons and purgatives. The DM must decide the exact strength of such poisons based on the poison rules in the DMG. A character with both herbalism and healing proficiencies gains bonuses when using his healing talent (see the Healing proficiency).
Player's Option: Skills & Powers[]
Herbalism: This skill indicates that a character is familiar with the uses of natural plant products for good and ill. If a character spends a day searching the woods, and makes a successful proficiency check, enough herbs, fungi, roots, leaves, pollen, and pulp has been gleaned for 2d6 doses.
The most common use of these herbs is as an aid to healing; one dose of herbs can be used in conjunction with the healing proficiency (by the herbalist or another healer). This dose adds +1 point to the wounds cured by a successful healing proficiency check. Even if the healing check fails, the herbs still restore the 1 hit point. With no healing proficiency, the herbs can still be used, but the herbalist needs to roll a successful check to restore the 1 hit point.
The herbs also can be used to create a poison, either ingested or injected. A single use of poison requires two doses of herbs. The lethality or other effects of the poison (paralysis, unconsciousness, delusions, etc.) must be worked out with the DM.
The Complete Thief's Handbook[]
Recommended: Assassin, Bounty Hunter.
A knowledge of herbs, particularly those with poisonous qualities, is of value to Assassins and Bounty Hunters. And Scouts often learn the types and properties of plants in their wilderness journeys. This proficiency is normally restricted to priests and wizards. Its description is on p. 59 of the Player's Handbook. See also p. 26 of this book for information on the use of this proficiency with the assassin thief kit.
The Complete Barbarian's Handbook[]
A barbarian may only identify and work with vegetation native to his homeland terrain. If he has both the herbalism and healing proficiencies, he may prepare and treat poisons in accordance to the restrictions outlined in the healing proficiency description above. With the DMs permission, assume that a barbarian carries a reasonable number of healing and poisonous herbs from his homeland.
Campaign Option: Council of Wyrms Setting[]
Herbalism allows a dragon to identify plants and fungi, and also prepare nonmagical potions, poultices, powders, balms, salves, and ointments for medical purposes. See the Player's Handbook for more details.
Hatchlings can't select this proficiency.