Richard B. Primack

Faculty Research Fellow
Professor of Biology, Boston University

Establishing a Pardee Center Working Group on Leaf Emergence and Fall (LEaF)

Warming temperatures are lengthening growing seasons in temperate ecosystems for most trees and shrubs — leaves are emerging earlier in spring and fall later in autumn. These seasonal shifts in leaf activity affect ecological relationships (e.g., species invasions and temporal mismatches among plants, insects, and birds), ecosystem processes (seasonal fluxes of carbon and water), and economic activities (e.g., urban tree investment and tourism to view fall foliage). These impacts, in turn, have important implications for policies regarding forestry, climate change mitigation and adaptation, and economic planning. The Pardee Leaf Emergence and Fall (LEaF) Working Group is gathering researchers from multiple departments at Boston University and neighboring institutions, all of whom study some aspect of the timing of leaf-out and leaf-fall, and facilitate dialogues with policy and management experts to accomplish three goals: (1) identify opportunities for interdisciplinary and synthetic collaboration; (2) articulate a research agenda that addresses critical needs and provides research support to graduate students and postdoctoral researchers address these needs; and (3) communicate insights gained from these activities through at least three peer-reviewed articles and several presentations and dialogues with land managers, policy makers, and other scientists. As part of this project, Prof. Primack convened a Working Group meeting at the Pardee Center which included 18 participants from Harvard, University of Massachusetts at Boston, the National Phenology Network, and BU in March 2017. For the past several months, the Working Group has been carrying out a variety of projects, most notably evaluating leaf characteristics in the Arnold Arboretum herbarium in relation to leaf-out times, and comparing leaf-out times in the spring using drones, field observations, and satellite data.


PhD, Duke University


Conservation biology, plant ecology, and climate change biology.


Richard Primack is a Professor of Biology at Boston University with research interests in plant ecology, conservation biology, climate change biology, citizen science, and tropical rain forests. He has published over 200 scientific papers, and carried out extensive fieldwork in Malaysia, New Zealand, Japan, Central America, United States, and other countries. He has served as the President of the Association for Tropical Biology and Conservation, and is an Honorary Fellow of that society. He has current appointments as the Distinguished Overseas Professor at the Northeast Forestry University in Harbin, China, and a Humboldt Research Awardee in Germany. He is the Editor-in-Chief of the international journal Biological Conservation and author of two widely used textbooks, Essentials of Conservation Biology and A Primer of Conservation Biology; for which 34 foreign language editions have been produced with local co-authors adding in examples from their own countries. He is also co-author of the book Tropical Rain Forests: An Ecological and Biogeographical Comparison.

For the past 14 years, Prof. Primack and his colleagues have been investigating the effects of a warming climate on the plants and birds of Massachusetts, with an emphasis on continuing the observations made 160 years ago by Henry David Thoreau in Concord. The work has also included experimental investigations of the environmental triggers of leaf out using dormant twigs, and the establishment of an international network of botanical gardens to monitor leaf out times in the spring and leaf senescence times in the autumn. Prof. Primack has been involved in educating the public about the effects of climate change through public talks and popular writing, including a recent book about his work: Walden Warming: Climate Change Comes to Thoreau’s Woods. His work has often been featured in the popular, including the New York Times, the Wall Street Journal, National Public Radio, and National Geographic magazine.

Prof. Primack has been selected as the Boston University Lecturer for 2016, and will present a lecture to the BU community and the public on October 26.