The main RuneScape Wiki has an article on: Guam leaf
The Old School RuneScape Wiki also has an article on Guam leaf.

A Guam leaf is a type of herb used in the Herblaw skill. It requires level 3 to identify and gives 2.5 Herblaw experience. It is used in making attack potions, as well as Ogre potions at level 14 Herblaw, which are used by the player during the Watchtower quest.

Dropped by

Herbs are always dropped by monsters in their unidentified forms

Monster Combat level Quantity Rarity
Chaos Druid 19 1–2* 2Common

* it is possible to get two different herbs

Spawns in

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