Trout concentrate in the improved stetches and populations are spotty in the unimproved sections.
Much higher gradients and a lot more woods back home which creates habitat without any help. The streams don't pay all that much attention to structures anyway. They go where they want based on the laws of gravity. Most PA projects on freestone waters are high and dry and out of the channel within 3-5 years. But in Wisconsin, they are vital to good fisheries, and so are those who design and build them.