Travel Notes October 1, 2006 in the Detroit Free Press points out that with nearly 200 species of hardwood trees, Arkansas has one of the longest fall foliage seasons in the United States.

The reds, oranges and yellows of the U.S. autumn are now just a few weeks away and the article offers links to weekly fall color updates
Arkansas fall foliage reports are updated at 4 p.m. local time, each Thursday. The Web site also has suggested scenic routes for viewing the foliage.
Hopes are high for a brilliant fall foliage season this year in New Hampshire. Keep track of the color at the
New Hampshire foliage site.
Experience fall in Colorado with suggested trips on the
Colorado State Parks site. The perfect landscape for a weekend getaway but with the warning that fall colors are arriving early this year, so don't delay.

In the Green valley, rocky high, blog on the Activity Vacations Guide, two posts were published last fall about autumn color in the United States:
Fall in the Great Smoky MountainsNational Forest Fall, which includes a link to the National Forest Fall Foliage Hotspots website.