I have fished Spring Branch near Manchester, Iowa. Trout are stocked as fingerlings, so they are stream reared. There are rainbows, brookies, and some good sized browns. I haven't fished there for about three years, but it probably hasn't changed.
I drove down from southeast Nebraska to fish the four open days. Caught lots of fish. Small woolly buggers, Mike's mohair leeches, and small egg flies worked best in the morning. On Saturday afternoon I caught a bunch using a size 22 zebra midge. One fish was 18" long. I caught several on Sunday afternoon using a size 24 parachute BWO during a blue winged olive hatch. My four biggest fish were two 18 inchers, one 20 incher, and one 21 incher. Had a great time.