DENVER (AP) - Colorado forestry officials say the state's spruce beetle infestation worsened in 2018.

The Colorado State Forest Service said Thursday the pest was active on 278 square miles of high elevation lands last year. Since 2000, the beetle has damaged about 2,800 square miles. 

The agency said the roundheaded pine beetle and Douglas fir beetle damaged a combined 64 square miles last year.

The agency's annual report said that wildfires consumed the second-largest area in state history in 2018 but did not say how much land was affected.

The report blamed dense, unhealthy forests, drought, and warmer temperatures linked to climate change.

The agency said the losses could have been worse if not for thinning, fire breaks and other preventive work.

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