On Hot Trail Of Tiny Killer In Alaska.

Reports that millions of acres of white spruce trees on the Kenai Peninsula in Alaska are dead or dying because of an increased infestation of the spruce bark beetle. Views of botanist Edward Berg, who believes a succession of warm years in Alaska has allowed spruce bark beetles to thrive; Implications of Berg's theory; Affect of rising temperatures in Alaska; Role of global warming; Reactions to Berg's findings.