1.  [5] Denalan's Earth
2. Both of the following:
   •  [7] Timberling Sprouts
   •  [7] Timberling Seeds
3.  [7] Rellian Greenspyre
4.  [9] Tumors
5.  [9] Return to Denalan
6.  [9G] Oakenscowl

Completing the chain up to the  [7] Timberling Seeds and  [7] Timberling Sprouts quests opens up the following quests:

•  [10] The Glowing Fruit
•  [10] The Shimmering Frond
  •  [10] The Sprouted Fronds
•  [12] The Moss-twined Heart
  •  [12] Planting the Heart