Complex sentence: The understory in lodgepole pine forests can be sparse but includes grasses, forbs, huckleberries, and grouse whortleberry, although fires in these forests are typically lethal to trees and understories alike.
Split into simpler sentences: The understory in lodgepole pine forests can be sparse but includes grasses, forbs, huckleberries, and grouse whortleberry. Fires in lodgepole pine-dominated forests are typically lethal to trees and understories alike.