Southeastern mixed forests grow in below the pines. Sugar maple ("Acer saccharum"), a shade tolerant tree, grows amid the oaks and hickories in the northern part of this ecoregion. Mesic forests occur in fertile, mesic, low-elevation habitats such as deep ravines and sheltered north- or east-facing slopes. Dominant trees include American beech ("Fagus grandifolia"), tulip tree ("Liriodendron tulipifera"), northern red oak, white ash ("Fraxinus americana"), black maple ("Acer nigrum"), sugar maple ("Acer saccharum"), basswood ("Tilia americana"), and bitternut hickory ("Carya cordiformis"). Understory trees include pawpaw ("Asimina triloba") and painted buckeye ("Aesculus sylvatica"). Mesic mixed hardwood forests grow on mesic uplands, ravines, lower slopes,
Fagus Factory one year before starting work on the Fagus factory) that architects should take account of the way the speed of modern transportation affects the way architecture is perceived. Gropius had also commented the subject in his writings. According to the historian of architecture Annemarie Jaeggi these thoughts were important in the design of Fagus: "The animated fluctuation in height, the change between horizontal structure and vertical rhythms, heavy closed volumes and light dissolved fabrics, are indicators of an approach that deliberately utilized contrasts while arriving at a harmony of opposites in a manner best expressed as a pictorial or visual