What are the West’s top must-have flies for trout? To find out, I consulted several of the region’s top fly fishermen. And though opinions varied, I was surprised by how often the choices aligned. Even when there was disagreement, it was usually only about variations on a pattern. And there was unanimous agreement that western trout flies need to be general in appeal, representing a wide variety of insects. Enter the following seven essential patterns. If you plan on tying up a storm this winter, these are flies you should have in your vest once spring arrives.