The fourth book in the Circle of Magic series by Tamora Pierce.
Briar, a young mage-in-training, and his teacher Rosethorn must use their magic to fight a deadly plague that is ravaging Summersea.
Briar, whose magic lies in the realm of plants, finds that a dear friend is suffering from a mysterious illness.
Briar's Book
The third book in the Circle of Magic series by Tamora Pierce.
Four young misfits find themselves living in a strictly disciplined temple community where they become friends while also learning to do crafts and to use their powers, especially magic.
But learning how to channel your power is vital. Evvy is a street urchin who doesn't even know she has stone magic, let alone know how to control it, and Briar's empathy with nature can heal - but it could kill just as easily. Ages 10+.
Her skill leaves others in awe, although controlling and channelling her power is second nature by now. And this is why she is horrified to find that an untrained boy, Pasco, is dancing complex magicwith no idea that he is doing it .
Tris is one of the most powerful mages ever born: her lightning magic flows through her veins and her bones.
The third book in an extraordinary fantasy quartet by acclaimed fantasy author Tamora Pierce.Daja and Frostpine expect to spend some peaceful weeks with old friends in Namorn.
Former 'street rat' Briar leads a comfortable life at Winding Circle Temple, learning plant magic from Rosethorn.