Information obtained from Oregon Hikers (https://www.oregonhikers.org/field_guide/Silver_Star_Mountain_via_Grouse_Vista_Hike)
Silver Star Mountain is one of the best 360 degree summits within a day's drive of Portland, boasting a rocky, exposed viewpoint of five major cascade volcanoes. It is also a great wildflower area in the spring, and huckleberries abound in the fall.
The Grouse Vista Trail option, from the south, is a little longer and more elevation gain than Silver Star from the north, but the Grouse Vista Trail road is easier. The Bluff Mountain trail is somewhat longer. The Grouse Vista trail is also the option with the most diverse terrain—alternating between exposure and shade, passing by large geologic formations, and keeping most of panoramic views available from the Silver Star summit under wraps until the final approach. The hike can probably be divided in three sections: 1) Steep and forested, 2) Exposed and flat, then 3) Very steep and in-and-out of the trees. Each section is just about a mile long.