The clusters of tiny yellow flowers on sassafras trees light up woodland edges and native landscapes in early spring, before the dogwoods bloom. Guy Sternberg, director of Starhill Forest Arboretum of Illinois College in Petersburg, especially likes the combination of sassafras flowers with redbud blooms: "like lemon-raspberry sherbet." Sassafras is native to North America and a host plant for the larvae of spicebush swallowtail butterfly and other butterflies and moths. Stephen Kress, vice president for bird conservation at the National Audubon Society, considers sassafras an excellent tree for attracting birds because of the high fat content of its fruit, which turns from green to dark purple in late summer; the fruit is consumed quickly and eagerly by resident and migrating birds. Sassafras trees have a willowy habit and grow quite tall, 30 to 60 feet, in sun or shade. Their leaves are rounded and mitten shaped, and turn brilliant scarlet or orange in early fall. They are difficult to transplant; start with seedlings or look for small specimens at garden shops. Hardy in USDA Plant Hardiness Zones 4 to 9.