The growing period of hardwood forests in eastern North America has increased by an average of one month over the past century as temperatures have steadily risen, a new study has found.
The study compared present-day observations of the time span from budburst to peak leaf coloration in seven tree species to similar documentation that was collected by an Ohio farmer at the turn of the 20th century.
An analysis of changes in those leaf patterns along with decades of temperature data for northwest Ohio showed a clear connection between increased warming during winter and spring and an extended period of tree growth.
The implications of the longer growing period – both positive and negative – remain unknown. But the simple fact that leaves stay on trees about 15% longer than they did 100 years ago is an “obvious indicator that temperatures are changing and shows that things are not the way they used to be – they are profoundly different,” said lead author Kellen Calinger-Yoak, assistant professor of evolution, ecology and organismal biology at The Ohio State University.
Read more at Ohio State University
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