Glob. chang. biol. Glob. chang. biol. Chilling and forcing temperatures interact to predict the onset of wood formation in Northern Hemisphere conifers Delpierre N. Lireux S. Hartig F. Camarero J.J. Cheaib A. Cufar K. Cuny H. Deslauriers A. Fonti P. Gricar J. Huang J.G. Krause C. Liu G. de Luis M. Universidad de Zaragoza Mäkinen H. del Castillo E.M. Morin H. Nöjd P. Oberhuber W. Prislan P. Rossi S. Saderi S.M. Treml V. Vavrick H. Rathgeber C.B.K. 2019 research-article