Complex sentence: Logging in the area began around the same time to supply lumber to support the mining industries, with production peaking in the late 1910s and gradually trailing off during the 1920s and 1930s.
Split into simpler sentences: Logging in the area began around the same time to supply lumber to support the mining industries. Logging peaked in the late 1910s and gradually trailed off during the 1920s and 1930s.