Jack pine is another, and a nearly-extinct bird really depends on these trees. The Kirtland's Warbler relies on large stands of young jack pine trees, and jack pine cones only open in intense heat of forest fires. Really sad, the birds can't survive in super cold climates and only like reproducing in jack pine forests, so the ending ice age and the formation of the Great Lakes trapped the birds in the northern Lower Peninsula of Michigan. They can't move into the Upper Peninsula or Canada where jack pine is more common because it's too cold, and can't move further south because there aren't any jack pine forests further south.
As the number of wildfires has declined, so has the number of large stands of young jack pines. This has had a devastating impact on the Kirtland's Warbler, who already had their natural habitat decimated.
Aspen and lodgepole pine