I recently spent a few day trips fishing some of the limestone spring creeks in south central Pennsylvania. The Letort Spring Run and Big Springs are two fantastic streams in close proximity to Carlisle–add in Falling Springs Branch near Chambersburg and you have three of the best spring creeks east of the Rocky Mountains. Fishing these spring creeks is much different from your average trip to the Gunpowder River. This is mostly due to the change in water characteristics. The wild browns and rainbows that reside in these spring creeks demand extreme stealth and perfect presentation. With a narrow stream bed and excessive aquatic plant growth like cress beds, a perfect presentation can be hard to achieve. Add in strange currents and densely overhanging trees and catching trout can become difficult. Like the Gunpowder, trico mayflies are currently hatching out in the mornings on these spring creeks. The spinner falls have been thick but begin a little earlier, around 8 am. Small BWOs may start hatching as well if the bright sun changes to cloud cover and drizzle. Expect to see sporadic tan and brown caddis in the size # 16 range emerging throughout the afternoon. I have been doing well fishing small terrestrials like ants and beetles tight to the banks. A size # 18 black rubber leg Rainys foam beetle worked well underneath bridges and trees. As always, fish cress bugs and scuds in between the cress beds on these spring creeks. These small crustaceans account for a large portion of the trouts diet. On separate days I caught nearly a half dozen wild browns from Letort and Falling Springs. Most of the fish were in the 8 to 12 inch range. Falling Springs tends to produce more rainbows than the Letort and you can expect to catch many chunky bows in the 6 to 10 inch range. I did land a nicer wild rainbow of 15 inches in Falling Springs one afternoon. I lost a considerably larger fish of around 18 inches the same day while nymphing in a fast run. The fish easily broke me off on 6x tippet. Remember to wash your boots and waders in a salt solution, rinse with freshwater and allow ample drying time before heading to other streams after fishing in the Gunpowder. Its important that we try to control the spread of Didymo.