stylistic:tone, structural:summarization
Maintenance

Natural surface, single-track trails will require some ongoing maintenance. If the trail is properly designed and constructed, maintenance should be limited to clearing downed trees, trimming back brush and clearing drainages. Depending on location, if the trail is properly designed, there should be no need for major rework such as grading or erosion control efforts. Mountain trails which see both significant rainfall and human traffic may require "trail hardening" efforts to prevent further erosion. Most of the seemingly natural rock steps on the mountain trails of the northeast United States are the work of professional and volunteer trail crews.