A grimy fellstalk is a herb harvested from a fellstalk plant grown from a fellstalk seed in a herb patch, requiring level 91 Farming. A minimum of three grimy fellstalk are harvested at a time.
Grimy fellstalk can be stored in a herb bag. Up to 50 grimy fellstalk can be stored in the herb bag, and up to 100 can be stored in the upgraded herb bag. Players can only have one herb bag at a time.
Grimy fellstalk can be cleaned, requiring level 91 Herblore and yielding 16.8 Herblore experience. Clean fellstalk are required to craft prayer renewal potions.
Grimy fellstalk can be harvested from fellstalk plants grown in a herb patch. A fully grown fellstalk will yield a minimum of three grimy fellstalk at harvest. When picked, each grimy fellstalk gives 315.6 Farming experience.
Harvest yields for fellstalk plants are determined by a "harvest lives" system. Each fellstalk plant begins with 3 lives. Additional lives are added with the use of compost (+1 life), supercompost (+2 lives) and ultracompost (+3 lives). Every harvest action will roll a chance out of 255 on the specific patch's "Chance to Save", taking one of the harvest lives from the patch if it does not hit; the patch will be cleared when it runs out of lives. The "Chance to Save" is dependent on the player's Farming level.
Herb seeds, grimy herbs, clean herbs, unfinished potions, as well as herb farming patches have been recoloured to be more consistent. It should be much easier from now to tell them apart! Thanks to everyone who has given feedback via social media.