If you're staying in Issaquah, then jump on I-90 and go over the pass. At around Salmon LaSac area is good just for scouting around. Less undergrowth. But August you'll still see alot of hikers roaming the area and people who '4-wheeling' in their SUVs mainly Seattlites that wanna get out for the weekend. For desert like terrian, drive east alittle more andto Ellensburg and beyond. Thenortheastern part of the state(Winthorp, Kettle falls, etc.) is where mostwhitetails are taken but also has upland birds.

Actually, once you get past North Bend, you'll see more and more open country. The western part is too crowded and land prices are at a premium. But if you like duck hunting, its actually okay.