Young Brunette Girl Reveals On The Rocky Beach With Remains Of A Dead Tree

By providing both food and microhabitats for many species, coarse woody debris helps to maintain the biodiversity of forest ecosystems. Up to forty percent of all forest fauna is dependent on CWD. Studies in western North America showed that only five per cent of living trees consisted of living cells by volume, whereas in dead wood it was as high as forty percent by volume, mainly fungi and bacteria. Colonizing organisms that live on the remains of cambium and sapwood of dead trees aid decomposition and attract predators that prey on them and so continue the chain of metabolizing the biomass.
The list of organisms dependent on CWD for habitat or as a food source includes bacteria, fungi, lichens, mosses and other plants, and in the animal kingdom, invertebrates such as termites, ants, beetles, and snails, amphibians such as salamanders, reptiles such as the slow-worm, as well as birds and small mammals. One third of all woodland birds live in the cavities of dead tree trunks. Woodpeckers, tits, chickadees, and owls all live in dead trees, and grouse shelter behind woody debris.
Plants use coarse woody debris as habitat, often covering them with mosses and lichens. In some forests with dense ground cover or waterlogged soils, germination on top of CWD is a competitive advantage. Large fragments of CWD that provide such habitat for herbs, shrubs, and trees are called nurse logs. CWD can also protect young plants from herbivory damage by acting as barriers to browsing animals.
The persistence of coarse woody debris can shelter organisms during a large disturbance to the ecosystem such as wildfire or logging.