You can learn how to craft it from Survival trainer.
It's very useful trinket if you want to level up your Herbalism skill. Also, it's not unique so you can equip 2 to increase your Herbalism skill by 10. If you lack skill points to pick up a herb, just equip this trinket and you can grab it. But most importantly, you get skill point for doing so. It makes leveling herbalism much easier.
also pretty sure this upgrades later with ZG rep recipe into the trinket that increases chance of black lotus drops by 3x (like you use this to craft the other trinket)