[audio:http://wamcradio.org/EarthWise/wp-content/uploads/2012/05/EW-07-16-12-Deadwood-Streams.mp3|titles=EW 07-16-12 Deadwood (Streams)]
Imagine a stream with no plants at all. Water flows rapidly, tearing out a deep channel. Anything you put into the stream is subject to being moved out.
Fallen trees can transform streams, slowing the flow of water and allowing material to be retained within the system. Large logs can persist for decades—altering stream flow and creating micro-habitats for aquatic animals.
Pants flourish in pools of still water created by woody dams, making them important nursery refuge for amphibians and fish. Still and stable, they are ideal for spawning. They also provide habitat for insect larvae, many of which require stable temperature and flow.
While not a great food resource itself, woody debris serves as a net to catch other food resources. Next time you are near a stream, and you see a wood jam, notice the leaves and twigs caught in the wood. If you pull out a wad of leaves, you will find it is full of bugs that provide essential forage for fish and amphibians.
The angling community is very aware of the relationship between dead wood and fish. Learn the art casting near this ‘fish structure’ and you are more likely to reel in a trout.
Dead wood is also important on the shoreline. Fallen trees let animals move across streams. Logs at the water’s edge are a refuge for invertebrates that need to live outside of the water. And woody debris on banks enriches shoreline soils.
The next time you feel the urge to “tidy up” a woodland stream, resist it. And let dead wood continue to provide shelter, structure, and food.
Photo, taken on August 19, 2005, courtesy of Russ via Flickr.