Harry Murray of Murrays Fly Shop has a good tip about winter trout fishing and how to choose a baetis or a midge pattern. For anyone who may not be familiar with Harry and his son Jeff, these guys are extremely knowledgeable about trout and smallmouth bass fishing in particular, and in my experience they are very happy to share what they know with anyone who asks.
Fly Fishing – The View From Harry’s Window – Beatis or Midge.