Place of Origin:Unknown
Death: Unknown
Appears: Marlfox

Sollertree, ("Soll"), formerly known as "Skyspike," was a hedgehog recluse who was a good friend of Goodwife Brimm. He was the husband of Beechtip and fathered a daughter called Nettlebud. He carried a large club, but never used it violently, and kept a little frog he nicknamed Croikle as a pet.

Sollertree left his home to seek out some new trees for his family's garden. He returned with a sapling, only to find his wife was killed and his daughter kidnapped because vermin, led by the Marlfoxes, had attacked his home. Sollertree spent many seasons trying to find his daughter, but became hopelessly lost, and accidentally wandered right back to his old home. Realizing there was no chance he'd ever find her, he gave up the search. He decided to live as a hermit and tend his garden, including the sapling he'd discovered earlier, which grew into a fine healthy nut tree. He also renamed himself from Skyspike to Sollertree. This was his mispronunciation of the word "Solitary."

Later in life, he aided Song, Dann, Burble, and Dippler when they passed through his territory. He helped scare off some robbers, and showed the group the way to the river. The four travelers later found Nettlebud where the Marlfoxes had imprisoned her, and returned her home to her father. Sollertree and Nettlebud later visited Redwall Abbey together.