Complex sentence: With population and economic growth, the church demolished its historic log structure in the 1870s and replaced it with the timber-framed church, begun in 1874 and completed in the 1880s, that is in use today.
Split into simpler sentences: With population and economic growth, the church demolished its historic log structure in the 1870s. It replaced it with the timber-framed church, begun in 1874 and completed in the 1880s, that is in use today.