Head to The Elddar Grove in Qeynos Province District. The Guards are level 55 at the gates, Lower level characters can avoid the guards by going through the Peat bog to the Vermin's Snye to Down Below, then the Elddar Grove.
Click on the basement doors outside the In Range ammo shop in the Elddar Grove at Loc (575, -18, -398) and enter the instance The Seed of Tunarbos.
When you zone in there will be several aggressive creatures near the entrance.
You can invisible or stealth past most of the monsters in this instance.
The first floor has 2x house plants, 1x a Tunarian Alliance woodsman, and 1x a Tunarian Alliance chef who appear to have a maximum level of 70.
Grab the cooking oil on the barrels to the right of where you zoned in then take the stairs up to the second floor.
The second floor has 2x house plants, 1x a Tunarian Alliance woodsman, and 1x a Tunarian Alliance warden.
Kill the Tunarian Alliance warden and loot the key that drops from their chest.
Travel back downstairs and right click on the locked door then choose "Unlock".
There is a Tunarian Alliance gardener guarding the tree past the door.
Kill the gardener then click on the barrel of fertilizer to mix the cooking oil you collected earlier in with the barrel.
Click on the barrel once more to light the fuse and explode the barrel destroying the tree.
You can avoid fighting all but 3 mobs with invis/stealth or Chameleon potions and careful movement. Kill the 2 plants by the entrance. Grab the oil from as far away as allowable. Invis and head upstairs. Kill the Warden for the key. Unlock door, detonate the barrel and run out of the instance. 10 minutes and two or three invis Tops.
Don't assume your Invisibility will hold up when zoning into the instance. More often than not, it doesn't hold.
The table on the first floor is clickable but doesn't appear to serve any purpose for this quest.
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