The southeast slope of Oregon's Mt. Hood has an exceptional area for butterfly watching called High Prairie.  It's an easy hike and you'll see butterflies starting at the parking area.  If you continue up to Lookout Mountain, there are fantastic views as well.  One day I happened on this blue butterfly along the trail in a moist meadow.  There are many species of blues but they are difficult to identify without seeing the pattern on the underside--which is unique to each species.  This one is such an intense blue that finding it made the entire trip worthwhile.  It's no bigger than a quarter; the camera lets us see it from a new and vibrant perspective.  

If you visit High Prairie be sure to bring a camera along to take pictures, along with a wildflower guide, butterfly field guide, and notebook.  The months of July, August, and early September are best for flowers and butterflies.  You'll also get a good idea of plants to put in your garden to attract butterflies.  Here asters are prominent along with lupines, valerian, and arnica.  Click here for more information on gardening to attract butterflies.