This March Brown Emerger imitation is tied on a barbless AHREX FW511 in a size 12.
Try fishing this March Brown emerger with no fly dressing first. It will float for the first few casts and then it will slowly sink under the surface, this allows you to see which method works best and which the fish are interested in on that specific day. If you want your emerger to float high then use a powdered-style floatant to keep it riding high on the water.
Don't be too afraid to let the nymph sink slowly and then manipulate it with your fly rod to help it rise through the water column, this perfectly imitates the emerging insect.
This fly is only available in a size 12.