Early season is characterized by COOOOOL water, Lazy fish, and lack of food in the water.
Try chironomids, which hatch first,but if no action switch to leeches or scuds which overwinter
in adult form. Fish your flies slooooooow. The fish may be quite shallow looking for warm water
or they may be near the bottom in deeper water (which is often warmest this time of year).
You have to bonk em in the nose,they won't move far for a fly.