I actually like to place nesting helpers out but you need to be selective. DO NOT use dryer lint. I know you probably have heard this from me before, but it is too dusty with very small particles. Use things like various lenths of strings, feathers, natural wool, fur (bison, Alpaca, dog, etc) and cotton. I like to place it under the overhang of my deck. Over 50 species of North American birds have been documented using people provided nesting materials.