What Zen said, but I would add leech patterns ( a black Carey will do), damselfly nymphs ( a thin-bodied, green-olive Carey will do) and some gray nymphs, say #8 or #10 for the callibaetis hatch on the lakes nearest Cheney. Scud patterns would also be a good idea.

You might also check out the book Flies of the Northwest published by the Inland Empire (Spokane) fly club-- it's got lots of good, local patterns.