Washington ? Forest Service scientists predict wildfires will become more severe as a half-century-long dry spell persists, peaking with a fire of unprecedented size around 2035.

The blaze could destroy some 2.1 billion metric tons of trees and plants, according to computer models that monitor short-term and long-term weather patterns and predict the growth of vegetation in the national forests.

Mark Rey, the Agriculture Department undersecretary in charge of the Forest Service, told the House Agriculture Committee on Wednesday that the country was in the midst of a dry cycle after several decades of wetter-than-normal conditions through the 1970s. The dry cycle is expected to last for several more decades.

Coupled with aggressive firefighting efforts that have kept forests from burning naturally and a predicted warming trend that spurs growth of vegetation, wildfires are expected to be more severe in the coming decades.

“We’re going to experience some significant fire years for the foreseeable future,” Rey said, adding that the predicted fire around 2035 “is going to be a real corker.”

The Forest Service’s computer models were put together by agency scientists based in Corvallis, Ore.