Dust and noise issues are becoming a problem for hikers, bikers, and horseback riders along the Stanislaus National Forest trails. They´re having to compete with users of motorized vehicles, and a recent decision to begin using so-called Interface Trails has raised objections from over a dozen groups and individuals. They´re filing appeals with the U.S. Forest Service, primarily focusing on motorized trail use, according to rangers. The Interface area includes 77 miles of trail which are open to motorized users, from Hathaway Pines to White Pines. The appeals period continues through next Tuesday, which is the last day valid letters can be postmarked.