What replaced the small individual lumber mills of western Washington?

Northwest lumber industry

Explanation:

The small individual lumber mills of western Washington was used for lumbering activities due the presence of large trees/forests in the Washington. this activities were a source of income for the small individual lumber mills but their activities was not properly coordinated, and this prompted the government and major lumbering mills to come into play and take over almost all the lumbering activities in the area and in the process organize and preserve some forest areas for the purpose of preserving trees for lumbering as well. the Northwest lumber industry was able to come into Western Washington due to the presence of the railway reaching the northwest.