Catskill Blue Wing Olive is another excellent dry fly that should be in everybody's fly box. Imitating a baetis aka blue winged olive getting ready to leave the water. Hatches can begin as early as late September and continue until April but the best time to catch it  would be February and early March. I like to use 6x tapered leader and 6x tippet. When I use a small blue winged Olive like size 16, 18, 20 I will use a double dry set up with a larger more visible fly as the attractor fly like one of my rubber leg stimulators.