The Shenandoah National Park streams are in great shape whether you decide to go into the streams from the top or the bottom. There are many ants and inchworms along the streams that the trout actively feed upon. A ploy I find very effective when the inchworms are around is to present my fly onto the stream surface with a splash. This is easy to do with a roll cast or with a regular overhead cast incorporating a snap of the wrist as the line loop turns over. This often brings the trout running to take your inchworm. I did well on the Murray's Inchworm size 14 and Mr. Rapidan Ant size 14 & 16 earlier this week.
For more information on these streams--stop by the fly shop or see my book Trout Fishing in the Shenandoah National Park.