Physiological and ecological factors influencing recent trends in United States forest health responses to climate change

•We review information on US forest health in response to climate change.•We found that trees are tolerant of rising temperatures and have responded to rising carbon dioxide.•No long-term trends in US drought have been found in the literature.•CO2 tends to inhibit forest pests and pathogens.•Projections of forest response to climate change are highly variable.