The elders' notice was nailed to Cyan Thornwood's door when she came home from the market. She read it twice, hooves shifting on the moss. The parchment named the blight in the oldest trees and forbade any new business before the council until the sickness was stopped. Cyan's own petition, the one she had spent a season writing, was pinned beneath it like an afterthought. She wanted a seat at that council. She wanted to be the one they sent to speak with humans. Instead she was a blue-haired girl in a pastel sundress the elders called a costume, holding a notice that pushed her further from the table. She ducked through the doorway carved into the base of the old oak she lived in. Autumn light fell through the hollow. She tore off the shopping bag, kicked her satchel against the wall, and stood in front of her bookshelf. The top three shelves were satyr grimoires, tanned and cracked, the kind the elders respected. The bottom shelf held her human books, the ones she had smuggled back from three summers of trips beyond the grove. She ran a finger along their spines until she found the green one. Field Guide to Tree Blight Diagnosis. Dr. Eleanor Marsh, PhD. She had bought it in a university town for the price of two afternoons washing dishes. She pulled it down and sat on the floor. Cyan opened to the index. Cankers. Chlorosis. Fungal fruiting bodies. She thought of the sick tree at the grove's edge, the one the elders had roped off last week. Black bark. Sickly green patches that glowed in moonlight. The elders called it a curse and burned sage at its roots. The guide called it something else, on page eighty-four, with a photograph that matched. It listed three tests she could do with a knife, a jar, and vinegar from her kitchen. She read the page twice to be sure. Her hands were shaking, but not from fear. If she was right, she could name the sickness before sundown. If she was right, the elders would have to listen to the girl in the modern dress with the human book. If she was wrong, they would have another reason to keep her out. Cyan tore a strip from a blank page and marked the chapter. She stuffed the guide into her satchel with a paring knife and an empty jam jar. At the door she stopped, pulled the elders' notice from the nails, and folded it into her pocket. She would bring it back to them with an answer written under their warning. She stepped out into the grove and turned toward the roped-off tree.