GRAND JUNCTION, Colo. — A new report says abundant Colorado snowpack helped reduce 2019 bark beetle activity impacting trees, but the following wet spring contributed to tree defoliation. 

The Daily Sentinel reports the findings were part of an annual U.S. Forest Service and Colorado State Forest Service aerial survey evaluating forest health impacts from insects and disease. 

> The video above first aired last July and covers CSU researchers looking into the connection between climate change and spruce beetle outbreaks.

The report says there was a decline in tree mortality in 2019 due to bark beetles compared to 2018, but spruce, roundheaded and western pine beetles continue to expand. 

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The report says the cold, wet spring followed by warm rains led to fungi germinating on aspen leaves. 

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