Why do chickens need a sward under trees?
Trees in the outdoor run are beneficial to the welfare of chickens. The ancestors of domestic chickens roost in trees, and hens are happier and use more of the range when it is enriched with trees. However, one problem with including trees in the range is the lack of ground vegetation under the trees, due to reduced light levels and increased competition. Further, where the tree canopy opens unpalatable weeds, rather than grasses, may grow.