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Association between leaf senescence day of year (DOY) in 2012 and 2013 at the Arnold Arboretum, Beijing Botanical Garden, Berlin Botanic Garden and Ottawa Arboretum (R2 = 0·43, n = 1802, P < 0·0001), showing the sequence of leaf senescence of species between years at each site. Each point on the graph represents an individual species at a site.
