Climatic determinants of white spruce cone crops in the boreal forest of southwestern Yukon

A groundbreaking study reveals that white spruce cone crops in the boreal forest of southwestern Yukon are primarily influenced by weather conditions two years prior, challenging conventional assumptions. Researchers analyzed 26 years of data (1986–2011) from over 700 trees across multiple sites, finding that July and August temperatures from years t-1 and t-2, along with May precipitation from year t-2, explained 54% of cone crop variation. This contradicts the traditional view linking cone crops to summer weather in the current or previous year. The study also found no periodic pattern in cone crops, indicating synchronous large crops across the Kluane region. This is the first quantitative model for predicting white spruce cone crops, offering novel insights into boreal forest ecology.

Krebs, C. J., LaMontagne, J. M., Kenney, A. J., & Boutin, S. (2012). Climatic determinants of white spruce cone crops in the boreal forest of southwestern Yukon. Botany, 90(2), 113–119. https://doi.org/10.1139/b11-088