Below is a tip from Toms Simms which I am posting to help you during this time of the year.  Even if you don’t tie flies you should check out the link to get  a look at how the fly looks.

Tom

I saw a number of small, dark stoneflies when I was on the property Wednesday. I’ve seen them many times before, but have never tried to imitate them. I caught one and estimated it as a size 18-20. The wings were a dark, dun color and the abdomen was also dun-colored with a lighter segmentation. The fly on the following link should do a good job of imitating the natural.

Video Source:
http://flytyer.wordpress.com/2010/02/27/little-black-stonefly/

Tom Simms